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  • 1.
    Aminzadeh, Selda
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Haghniaz, R.
    Ottenhall, A.
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Lindström, E.
    Khademhosseini, A.
    Lignin based hydrogel for the antibacterial applicationManuscript (preprint) (Other academic)
  • 2.
    Aminzadeh, Selda
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Lauberts, M.
    Dobele, G.
    Ponomarenko, J.
    Mattsson, T.
    Lindström, Mikael
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Sevastyanova, Olena
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Membrane filtration of kraft lignin: Structural charactristics and antioxidant activity of the low-molecular-weight fraction2018In: Industrial crops and products (Print), ISSN 0926-6690, E-ISSN 1872-633X, Vol. 112, p. 200-209Article in journal (Refereed)
    Abstract [en]

    Lignin, which is the second most abundant biomass component and has carbon-rich phenolic content, is a promising renewable raw material for multiple applications, such as carbon fibers, adhesives, and emulsifiers. To use lignin efficiently, it is important to ensure its purity and homogeneity. As a result, the separation of lignin into fractions with high purity and narrow molecular-weight distributions is likely a prerequisite for several applications. Ultrafiltration using ceramic membranes has many advantages, including enabling direct lignin extraction from Kraft pulp cooking liquors without pH and temperature adjustment. One challenge with membrane filtration using such a system is the potential for reduced membrane performance over time, which is associated with fouling. In this study, LignoBoost Kraft lignin was fractionated using a ceramic membrane with a molecular weight cut-off of 1 kDa. The separation behavior during ultrafiltration fractionation was investigated and the antioxidant properties of the recovered low-molecular-weight (low-MW) lignin samples were evaluated. Using this model system, the permeate fluxes were unstable during the 100 h of membrane operation. However, a decrease in the average MW in the permeate over time was observed. The shift in MW was most pronounced for virgin membranes, while a more stable MW distribution was evident for membranes subjected to multiple cleaning cycles. According to 2D NMR analysis, low-MW lignin that was recovered after 100 h of operation, consisted of smaller lignin fragments, such as dimers and oligomers, with a high content of methoxy-groups. This was confirmed using the size exclusion chromatography method, which indicated an weigh average molecular weight in the range of 450–500 Da. 31P NMR spectroscopy showed that, despite the lower total content of phenolic OH groups, the low-MW sample had a higher proportion of non-condensed phenolic OH groups. The results of the antioxidant tests demonstrated the strong potential of lignin and its low-MW fraction as a natural antioxidant, particularly for lipid-containing systems. The low-MW lignin fraction showed better antioxidant activity than the non-fractionated LignoBoost lignin in the kinetic oxygen radical absorbance capacity (ORAC) test and demonstrated three-fold stronger inhibition of the substrate (fluorescein) than the reference antioxidant Trolox (a water-soluble derivative of vitamin E).

  • 3. Andersson, Alexander
    et al.
    Vegunta, Vijaya
    Lindström, Mikael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology.
    Jansson, Ulla
    Henriksson, Gunnar
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology.
    Presence of Calcium Cations Stimulate Alkaline Hydrolysis of Cellulose During Kraft Pulping ConditionsManuscript (preprint) (Other academic)
    Abstract [en]

    Simulated kraft pulping has been performed on cotton linters fibers consisting of almost pure cellulose with varying content of calcium ions. These concentrations were obtained by soaking and drying cotton linters in calcium sulfate solutions. The viscosities of the pulped fibers were generally lower with higher calcium ion concentration and, therefore, in line with earlier suggested ideas that calcium ions could catalyze alkaline hydrolysis. The technical importance of these results is discussed.

  • 4.
    Budnyak, Tetyana
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Aminzadeh, Selda
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Pylypchuk, Ievgen
    Department of Molecular Sciences, Swedish University of Agricultural Sciences (SLU), Allmas alle 5, SE-750 07 Uppsala, Swede.
    Riazanova, Anastasiia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Tertykh, Valentin
    Chuiko Institute of Surface Chemistry, National Academy of Sciences of Ukraine, 17 General Naumov Str., 03164 Kyiv, Ukraine.
    Lindström, Mikael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Peculiarities of synthesis and properties of lignin-silica nanocomposites prepared by sol-gel method2018In: Nanomaterials, E-ISSN 2079-4991, Vol. 8, no 11, p. 1-18, article id 950Article in journal (Refereed)
    Abstract [en]

    The development of advanced hybrid materials based on polymers from biorenewable sources and mineral nanoparticles is currently of high importance. In this paper, we applied softwood kraft lignins for the synthesis of lignin/SiO2 nanostructured composites. We described the peculiarities of composites formation in the sol-gel process through the incorporation of the lignin into a silica network during the hydrolysis of tetraethoxysilane (TEOS). The initial activation of lignins was achieved by means of a Mannich reaction with 3-aminopropyltriethoxysilane (APTES). In the study, we present a detailed investigation of the physicochemical characteristics of initial kraft lignins and modified lignins on each step of the synthesis. Thus, 2D-NMR, P-31-NMR, size-exclusion chromatography (SEC) and dynamic light scattering (DLS) were applied to analyze the characteristics of pristine lignins and lignins in dioxan:water solutions. X-Ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR) were used to confirm the formation of the lignin-silica network and characterize the surface and bulk structures of the obtained hybrids. Termogravimetric analysis (TGA) in nitrogen and air atmosphere were applied to a detailed investigation of the thermal properties of pristine lignins and lignins on each step of modification. SEM confirmed the nanostructure of the obtained composites. As was demonstrated, the activation of lignin is crucial for the sol-gel formation of a silica network in order to create novel hybrid materials from lignins and alkoxysilanes (e.g., TEOS). It was concluded that the structure of the lignin had an impact on its reactivity during the activation reaction, and consequently affected the properties of the final hybrid materials.

    Download full text (pdf)
    Peculiarities of Synthesis and Properties of Lignin–Silica Nanocomposites Prepared by Sol-Gel Method
  • 5.
    Budnyak, Tetyana M.
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. Natl Acad Sci Ukraine, Chuiko Inst Surface Chem, 17 Gen Naumov Str, UA-03164 Kiev, Ukraine..
    Aminzadeh, Selda
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Pylypchuk, Ievgen V.
    Swedish Univ Agr Sci SLU, Dept Mol Sci, Allmas Alle 5, SE-75007 Uppsala, Sweden..
    Sternik, Dariusz
    Marie Curie Sklodowska Univ, 2 M Curie Sklodowska Sq, PL-20031 Lublin, Poland..
    Tertykh, Valentin A.
    Natl Acad Sci Ukraine, Chuiko Inst Surface Chem, 17 Gen Naumov Str, UA-03164 Kiev, Ukraine..
    Lindström, Mikael E.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Methylene Blue dye sorption by hybrid materials from technical lignins2018In: Journal of Environmental Chemical Engineering, E-ISSN 2213-3437, Vol. 6, no 4, p. 4997-5007Article in journal (Refereed)
    Abstract [en]

    New hybrid sorbents were synthesized from technical lignins and silica and were applied for the removal of Methylene Blue dye (MB) from aqueous solution. Kraft softwood lignins from LignoBoost (LBL) and CleanFlowBlack (CFBL) processes were used to understand the influence of molecular weight and functionality of initial lignins on the properties of the final hybrids. The synthesized materials were applied as adsorbents for the removal of MB from aqueous solutions. The effects of parameters such as contact time, initial concentration of dye and initial pH on the adsorption capacity were evaluated. The hybrids exhibited higher adsorption capacity than the initial macromolecules of lignin with respect to MB. The hybrid based on CFBL exhibited an adsorption capacity of 60 mg/g; this value was 30% higher than the capacity of the hybrid based on LBL, which was 41.6 mg/g. Lignin hybrid materials extract 80-99% of the dye in a pH range from 3 to 10. The equilibrium and kinetic characteristics of MB uptake by the hybrids followed the Langmuir isotherm model and pseudosecond-order model, rather than the Freundlich and Temkin models, the pseudo-first-order or the intraparticle diffusion model. The attachment of the dye to the hybrid surface was confirmed via FE-SEM and FTIR spectroscopy. The mechanism for MB adsorption was proposed. Due to the high values of regeneration efficiency of the surface of both lignin-silica hybrid materials in 0.1 M HCl (up to 75%) and ethanol (99%), they could be applied as effective sorbents in industrial wastewater treatment processes.

  • 6.
    Budnyak, Tetyana M.
    et al.
    Stockholm Univ, Dept Mat & Environm Chem, S-10691 Stockholm, Sweden..
    Modersitzki, Sina
    Stockholm Univ, Dept Mat & Environm Chem, S-10691 Stockholm, Sweden..
    Pylypchuk, Ievgen
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology.
    Piatek, Jedrzej
    Stockholm Univ, Dept Mat & Environm Chem, S-10691 Stockholm, Sweden..
    Jaworski, Aleksander
    Stockholm Univ, Dept Mat & Environm Chem, S-10691 Stockholm, Sweden..
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Lindström, Mikael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Slabon, Adam
    Stockholm Univ, Dept Mat & Environm Chem, S-10691 Stockholm, Sweden..
    Tailored Hydrophobic/Hydrophilic Lignin Coatings on Mesoporous Silica for Sustainable Cobalt(II) Recycling2020In: ACS Sustainable Chemistry and Engineering, E-ISSN 2168-0485, Vol. 8, no 43, p. 16262-16273Article in journal (Refereed)
    Abstract [en]

    Lignin is a renewable biopolymer, and its chemical functionalization renders it a prospective material for a plethora of applications. Within this respect, we present a method for lignin immobilization on the surface of mesoporous silica. Two types of lignins were used to prove the feasibility of the fabrication of either hydrophilic or hydrophobic biocoatings on silica. The procedure permits to immobilize 17 mg of lignosulfonate (LS) or 37 mg of kraft lignin (KL) per gram of silica. The bioinorganic composites display a synergistic effect in the adsorption of cobalt(II) ions from aqueous solutions because the adsorption efficiency outperforms the individual constituents. These results demonstrate that thin lignin overlayers, exhibiting polymer concentrations of 0.07 mg.m(-2) for LS-SiO2, and 0.14 mg.m(-2) for KL-SiO2, provide new functionality in comparison to bulk lignin and metal oxides. According to the Langmuir isotherm model, the adsorption capacity toward aqua complexes of Co(II) was found to be 75 and 59 mg.g(-1) for the LS- or KL-coated silica, respectively. The kinetic study revealed that lignin-SiO2 composites gained the features of inorganic sorbents because 1-1.5 h was sufficient for effective cobalt extraction. The adsorption on the bioinorganic composites proceeds with the pseudo-second-order kinetics model. The adsorption of Co(II) ions was confirmed by means of solid-state H-1 magic-angle spinning (MAS) NMR spectroscopy. The simplicity of the synthesis, low-cost and abundancy of substrates, high capacity, and fast kinetics make such lignin-coated silica a promising material for cobalt recovery.

  • 7.
    Budnyak, Tetyana M.
    et al.
    Stockholm Univ, Dept Mat & Environm Chem, Svante Arrhenius Vag 16C, S-10691 Stockholm, Sweden..
    Onwumere, Joy
    Stockholm Univ, Dept Mat & Environm Chem, Svante Arrhenius Vag 16C, S-10691 Stockholm, Sweden..
    Pylypchuk, Ievgen, V
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology.
    Jaworski, Aleksander
    Stockholm Univ, Dept Mat & Environm Chem, Svante Arrhenius Vag 16C, S-10691 Stockholm, Sweden..
    Chen, Jianhong
    Stockholm Univ, Dept Mat & Environm Chem, Svante Arrhenius Vag 16C, S-10691 Stockholm, Sweden..
    Rokicinska, Anna
    Stockholm Univ, Dept Mat & Environm Chem, Svante Arrhenius Vag 16C, S-10691 Stockholm, Sweden..
    Lindström, Mikael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Kustrowski, Piotr
    Jagiellonian Univ, Fac Chem, Gronostajowa 2, PL-30387 Krakow, Poland..
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. Jagiellonian Univ, Fac Chem, Gronostajowa 2, PL-30387 Krakow, Poland..
    Slabon, Adam
    Stockholm Univ, Dept Mat & Environm Chem, Svante Arrhenius Vag 16C, S-10691 Stockholm, Sweden..
    LignoPhot: Conversion of hydrolysis lignin into the photoactive hybrid lignin/Bi4O5Br2/BiOBr composite for simultaneous dyes oxidation and Co2+ and Ni2+ recycling2021In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 279, article id 130538Article in journal (Refereed)
    Abstract [en]

    Valorization of lignin is still an open question and lignin has therefore remained an underutilized biomaterial. This situation is even more pronounced for hydrolysis lignin, which is characterized by a highly condensed and excessively cross-linked structure. We demonstrate the synthesis of photoactive lignin/Bi4O5Br2/BiOBr bio-inorganic composites consisting of a lignin substrate that is coated by semiconducting nanosheets. The XPS analysis reveals that growing these nanosheets on lignin instead on cellulose prevents the formation of Bi5+ ions at the surface region, yielding thus a modified hetero-junction Bi4O5Br2/BiOBr. The material contains 18.9% of Bi4O5Br2/BiOBr and is effective for the photocatalytic degradation of cationic methylene blue (MB) and zwitterionic rhodamine B (RhB) dyes under light irradiation. Lignin/Bi4O5Br2/BiOBr decreases the dye concentration from 80 mg L-1 to 12.3 mg L-1 for RhB (85%) and from 80 mg L-1 to 4.4 mg L-1 for MB (95%). Complementary to the dye degradation, the lignin as a main component of the composite, was found to be efficient and rapid biosorbent for nickel, lead, and cobalt ions. The low cost, stability and ability to simultaneously photo-oxidize organic dyes and adsorb metal ions, make the photoactive lignin/Bi4O5Br2/BiOBr composite a prospective material for textile wastewaters remediation and metal ions recycling.

  • 8.
    Budnyak, Tetyana M.
    et al.
    Stockholm Univ, Dept Mat & Environm Chem, S-10691 Stockholm, Sweden..
    Piatek, Jeddrzej
    Stockholm Univ, Dept Mat & Environm Chem, S-10691 Stockholm, Sweden..
    Pylypchuk, Ievgen, V
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology.
    Klimpel, Matthias
    Stockholm Univ, Dept Mat & Environm Chem, S-10691 Stockholm, Sweden..
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Lindström, Mikael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Gun'ko, Volodymyr M.
    Natl Acad Sci Ukraine, Chuiko Inst Surface Chem, UA-03164 Kiev, Ukraine..
    Slabon, Adam
    Stockholm Univ, Dept Mat & Environm Chem, S-10691 Stockholm, Sweden..
    Membrane-Filtered Kraft Lignin-Silica Hybrids as Bio-Based Sorbents for Cobalt(II) Ion Recycling2020In: ACS Omega, E-ISSN 2470-1343, Vol. 5, no 19, p. 10847-10856Article in journal (Refereed)
    Abstract [en]

    Efficient and sustainable recycling of cobalt(II) is of increasing importance to support technological development in energy storage and electric vehicle industries. A composite material based on membrane-filtered lignin deposited on nanoporous silica microparticles was found to be an effective and sustainable sorbent for cobalt(II) removal. This bio-based sorbent exhibited a high sorption capacity, fast kinetics toward cobalt(II) adsorption, and good reusability. The adsorption capacity was 18 mg Co(II) per gram of dry adsorbent at room temperature (22 degrees C) at near-neutral pH, three times higher than that of the summarized capacity of lignin or silica starting materials. The kinetics study showed that 90 min is sufficient for effective cobalt(II) extraction by the composite sorbent. The pseudo-second-order kinetics and Freundlich isotherm models fitted well with experimentally obtained data and confirmed heterogeneity of adsorption sites. The promising potential of the lignin-silica composites for industrial applications in the cobalt recovering process was confirmed by high values of desorption in mildly acidic solutions.

  • 9.
    Budnyak, Tetyana M.
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. Department of Materials and Environmental Chemistry, Stockholm University, Svante Arrhenius väg 16 C, Stockholm, 106 91, Sweden.
    Pylypchuk, Ievgen, V
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Lindström, Mikael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Electrostatic Deposition of the Oxidized Kraft Lignin onto the Surface of Aminosilicas: Thermal and Structural Characteristics of Hybrid Materials2019In: ACS Omega, E-ISSN 2470-1343, Vol. 4, no 27, p. 22530-22539Article in journal (Refereed)
    Abstract [en]

    In recent years, functional polymeric compounds have been widely used to modify the silica surface, which allows one to obtain the corresponding organomineral composites for broad application prospects. In this case, lignin-a cross-linked polyphenolic macromolecule-is of great interest according to its valuable properties and possible surplus as a by-product of pulp and paper industry and various biorefinery processes. Hybrid materials based on kraft softwood lignin and silica were obtained via the electrostatic attraction of oxidized lignin to the aminosilica surface with different porosities, which were prepared by the amination of the commercial silica gel with an average pore diameter of 6 nm, and the silica prepared in the lab with the oxidized kraft lignin and lignin-silica samples with an average pore diameter of 38 nm was investigated by physicochemical methods: two-dimensional nuclear magnetic resonance (NMR), P-31 NMR, Fourier transform infrared spectroscopy, thermogravimetric analysis in nitrogen and air atmosphere, scanning electron microscopy, and adsorption methods. After oxidation, the content of carboxylic groups almost doubled in the oxidized lignin, compared to that in the native one (0.74 mmol/g against 0.44 mmol/g, respectively). The lignin content was deposited onto the surface of aminosilica, depending on the porosity of the silica material and on the content of amino groups on its surface, giving lignin-aminosilica with 20% higher lignin content than the lignin-aminosilica gel. Both types of lignin-silica composites demonstrate a high sorptive capacity toward crystal violet dye. The suggested approach is an easy and low-cost way of synthesis of lignin-silica composites with unique properties. Such composites have a great potential for use as adsorbents in wastewater treatment processes.

  • 10.
    Cederholm, Linnea
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymer Technology.
    Xu, Yunsheng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Tagami, Ayumu
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymer Technology.
    Odelius, Karin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Hakkarainen, Minna
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymer Technology.
    Microwave processing of lignin in green solvents: A high-yield process to narrow-dispersity oligomers2020In: Industrial crops and products (Print), ISSN 0926-6690, E-ISSN 1872-633X, Vol. 145, article id 112152Article in journal (Refereed)
    Abstract [en]

    Functional narrow-dispersity kraft lignin oligomers in high-yields were produced by a combined microwave-assisted extraction/degradation process. The process took place under mild non-catalytic conditions, in green solvents, and moderate temperatures (80 -160 degrees C). High yields, i.e., 63 % and 64 %, of lignin oligomers with narrow dispersity were obtained after only 40 min microwave processing in methanol and ethanol, respectively. The ethanol-soluble yield increased substantially after microwave processing as compared to samples extracted by liquid-solid solvent-extraction. This increase was mainly ascribed to the cleavage of beta-O-4 linkages, as indicated by semiquantitative 2D-HSQC NMR. Under the corresponding conditions in methanol, the yields after microwave processing were similar to those obtained by liquid-solid solvent-extraction. The difference is likely ascribed to the different reactivities of the solvents as O-alkylation agents. Furthermore, the obtained lignin fractions had high functionality, as shown by hydroxyl-group quantification through P-31-NMR. This, along with the narrow dispersity and rich aromatic structure, makes these oligomers interesting precursors for future thermoset syntheses.

  • 11.
    de Carvalho, Danila Morais
    et al.
    KTH, Royal Inst Technol, Dept Fibre & Polymer Technol, SE-10044 Stockholm, Sweden.;KTH, Royal Inst Technol, Dept Fibre & Polymer Technol, Wallenberg Wood Sci Ctr, SE-10044 Stockholm, Sweden.;Univ Helsinki, Dept Food & Nutr, FI-00014 Helsinki, Finland..
    Berglund, Jennie
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Marchand, Celia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Lindström, Mikael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Vilaplana, Francisco
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Improving the thermal stability of different types of xylan by acetylation2019In: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344, Vol. 220, p. 132-140Article in journal (Refereed)
    Abstract [en]

    The impact of various degrees of acetylation on improving the thermal stability of xylan isolated from different botanical source has been studied; methylglucuronoxylan from birch and eucalyptus, arabinoglucuronoxylan from spruce and glucuronoarabinoxylan from sugarcane bagasse and straw. The lower molecular weight of nonacetylated methylglucuronoxylan (17.7-23.7 kDa) and arabinoglucuronoxylan (16.8 kDa) meant that they were more soluble in water than glucuronoarabinoxylan (43.0-47.0 kDa). The temperature at the onset of degradation increased by 17-61 degrees C and by 75-145 degrees C for low and high acetylated xylans respectively, as a result of acetylation. A glass transition temperature in the range of 121-132 degrees C was observed for the samples non-acetylated and acetylated at low degree of acetylation (0.0-0.6). The acetylation to higher degrees (1.4-1.8) increased the glass transition temperature of the samples to 189-206 degrees C. Acetylation proved to be an efficient method for functionalization of the xylan to increase the thermal stability.

  • 12.
    de Carvalho, Danila Morais
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. University of Helsinki, Finland.
    Marchand, Celia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology. Graduate School of Engineering in Paper, Print Media and Biomaterials, Grenoble INP-Pagora, Grenoble, 38402, France.
    Berglund, Jennie
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Lindström, Mikael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Vilaplana, Francisco
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Glycoscience. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Impact of birch xylan composition and structure on film formation and properties2020In: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 74, no 2, p. 184-196Article in journal (Refereed)
    Abstract [en]

    Commercial birch xylan (CX) and alkali-soluble birch xylan (ASX) were subjected to controlled acetylation and used for film formation in the presence (20% and 40%) or absence of plasticizers (i.e. glycerol, sorbitol and xylitol). Although the content of Klason lignin was similar (1.2-1.4%), the acetylation process was favored by the high-purity CX (97% xylan) over the ASX (89% xylan). On the other hand, the presence of residual pectin heteropolysaccharides rather than xylan in the ASX sample was beneficial for film formation. These heteropolysaccharides seemed to act as natural plasticizers during film formation, allowing the formation of coherent films from ASX, even in the absence of an external plasticizer. The use of plasticizers favored the mechanical properties of films, especially in a dosage of 40%, when plastic behavior was created. Acetylation favored the film formation and slightly improved the mechanical properties of the films, and this improvement was in the same range as that achieved when using 20% plasticizer in non-acetylated ASX.

  • 13.
    de Carvalho, Danila Morais
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology. KTH, Stockholm, Sweden.;Univ Fed Vicosa, Vicosa, MG, Brazil..
    Martinez-Abad, Antonio
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. KTH, Stockholm, Sweden..
    Colodette, Jorge Luiz
    Univ Fed Vicosa, Vicosa, MG, Brazil..
    Lindström, Mikael
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. KTH, Stockholm, Sweden..
    Vilaplana, Francisco
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. KTH, Stockholm, Sweden..
    Sevastyanova, Olena
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. Fibre Wood Tech Wood Chem Pulp Tech, Stockholm, Sweden..
    Chemical and structural characterization of xylans from sugarcane bagasse and sugarcane straw2016In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 251Article in journal (Other academic)
  • 14.
    de Carvalho, Danila Morais
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology.
    Moser, Carl
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology.
    Lindström, Mikael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology.
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology.
    Impact of the chemical composition of cellulosic materials on the nanofibrillation process and nanopaper properties2019In: Industrial crops and products (Print), ISSN 0926-6690, E-ISSN 1872-633X, Vol. 127, p. 203-211Article in journal (Refereed)
    Abstract [en]

    This paper investigated the impact of the amounts of lignin and hemicelluloses on cellulose nanofibers (CNFs). Birch and spruce wood were used to prepare holocellulose and cellulose samples by classical methods. To better assess the effect of the chemical composition on the CNF performance and simplify the process for CNF preparation, no surface derivatization method was applied for CNF preparation. Increased amounts of hemicelluloses, especially mannans, improved the defibration process, the stability of the CNFs and the mechanical properties, whereas the residual lignin content had no significant effect on these factors. On the other hand, high lignin content turned spruce nanopapers yellowish and, together with hemicelluloses, reduced the strain-at-break values. Finally, when no surface derivatization was applied to holocellulose and cellulose samples before defibration, the controlled preservation of residual lignin and hemicelluloses on the CNFs indicate to be crucial for the process. This simplified method of CNF preparation presents great potential for forest-based industries as a way to use forestry waste (e.g., branches, stumps, and sawdust) to produce CNFs and, consequently, diversify the product range and reach new markets.

  • 15. de Carvalho, Danila Morais
    et al.
    Sevastyanova, Olena
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    de Queiroz, Jose Humberto
    Colodette, Jorge Luiz
    Cold alkaline extraction as a pretreatment for bioethanol production from eucalyptus, sugarcane bagasse and sugarcane straw2016In: Energy Conversion and Management, ISSN 0196-8904, E-ISSN 1879-2227, Vol. 124, p. 315-324Article in journal (Refereed)
    Abstract [en]

    Optimal conditions for the cold alkaline extraction (CAE) pretreatment of eucalyptus, sugarcane bagasse and sugarcane straw are proposed in view of their subsequent bioconversion into ethanol through the semi -simultaneous saccharification and fermentation (SSSF) process (with presaccharification followed by simultaneous saccharification and fermentation, or SSF). The optimum conditions, which are identified based on an experiment with a factorial central composite design, resulted in the removal of 46%, 52% and 61% of the xylan and 15%, 37% and 45% of the lignin for eucalyptus, bagasse and straw, respectively. The formation of pseudo-extractives was observed during the CAE of eucalyptus. Despite the similar glucose concentration and yield for all biomasses after 12 h of presaccharification, the highest yield (0.065 g(ethanol)/g(biomass)), concentrations (5.74 g L-1) and volumetric productivity for ethanol (0.57 g L-1 h(-1)) were observed for the sugarcane straw. This finding was most likely related to the improved accessibility of cellulose that resulted from the removal of the largest amount of xylan and lignin.

  • 16.
    Esteves, Claudia
    et al.
    388792 RISE Research Institutes of Sweden , Bioeconomy and Health, Pulp, Paper and Packaging , Drottning Kristinas väg 61 , Stockholm , Sweden.
    Brännvall, Elisabet
    388792 RISE Research Institutes of Sweden , Bioeconomy and Health, Pulp, Paper and Packaging , Drottning Kristinas väg 61 , Stockholm , Sweden.
    Östlund, Sören
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics, Vehicle Engineering and Solid Mechanics, Solid Mechanics.
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology.
    The effects of high alkali impregnation and oxygen delignification of softwood kraft pulps on the yield and mechanical properties2022In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 37, no 2, p. 223-231Article in journal (Refereed)
    Abstract [en]

    This study investigated whether the yield improvement after high alkali impregnation (HAI) is maintained after oxygen delignification and whether the potential of oxygen delignification to increase the mechanical properties is affected by high alkali impregnation. The yield improvement achieved by high alkali impregnation (1 %) was preserved after oxygen delignification, particularly of glucomannan. The total fiber charge and swelling increased after oxygen delignification regardless of the type of impregnation in the cooking step. The tensile index improvement obtained by oxygen delignification was retained if this was preceded by high alkali impregnation. The stiffness index was higher and elongation slightly lower after HAI impregnation than after a standard (REF) impregnation. Fibers obtained through high alkali impregnation seem to be slightly less deformed and slightly wider than fibers obtained after a standard impregnation.

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  • 17.
    Esteves, Cláudia S. V. G.
    et al.
    RISE INNVENTIA AB, Drottning Kristinas väg 61, SE-114 28 Stockholm, Sweden.
    Brännvall, Elisabet
    RISE INNVENTIA AB, Drottning Kristinas väg 61, SE-114 28 Stockholm, Sweden.
    Östlund, Sören
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics, Vehicle Engineering and Solid Mechanics, Solid Mechanics.
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Evaluating the Potential to Modify Pulp and Paper Properties through Oxygen Delignification2020In: ACS Omega, E-ISSN 2470-1343, Vol. 5, no 23, p. 13703-13711Article in journal (Refereed)
    Abstract [en]

    The potential to modify pulp and paper properties by oxygen delignification was assessed by looking beyond the ordinary purpose of oxygen delignification. Pulps with the same kappa number were obtained by both pulping and the combination of pulping and oxygen delignification, and the mechanical and chemical properties were compared. The oxidation of pulp components leads to an increase in carboxylic acid groups in the fibers, resulting in a large influence on fiber swelling, seen as an increase in the water retention value and fiber saturation point. The introduction of charged groups appears to replace some of the morphological changes caused by refining and enhance the strength of fiber–fiber joints, generating pulps with better refinability and higher tensile strength. Oxygen delignification was able to improve the tensile index with 6% at the same sheet density and less refining energy, when the amount of total fiber charges was higher than 140 μekv/g.

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  • 18. Esteves, Cláudia S. V. G.
    et al.
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Östlund, Sören
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics, Vehicle Engineering and Solid Mechanics, Solid Mechanics.
    Brännvall, Elisabet
    RISE.
    Differences and similarities between kraft and oxygen delignification of softwood fibers: effects on chemical and physical properties2021In: Cellulose, ISSN 0969-0239, E-ISSN 1572-882X, Cellulose, Vol. 28, no 5, p. 3149-3167Article in journal (Refereed)
    Abstract [en]

    The fiber properties after oxygen delignification and kraft pulping were studied by looking into the chemical characteristics and morphology. The effect of the two processes on the fibers was evaluated and compared over a wider kappa number range (from 62 down to15). Wide-angle X-ray scattering, nuclear magnetic resonance and fiber saturation point were used to characterize the fiber network structure. Fiber morphology and fiber dislocations were evaluated by an optical image analysis. The total and surface fiber charges were studied by conductometric and polyelectrolyte titrations. The fiber wall supramolecular structure, such as crystallinity, size of fibril aggregates, pore size and pore volume, were similar for the two processes. The selectivity, in terms of carbohydrate yield, was equal for kraft cooking and oxygen delignification, but the selectivity in terms of viscosity loss per amount of delignification is poorer for oxygen delignification. Clearly more fiber deformations (2–6% units in curl index) in the fibers after oxygen delignification were seen. Introduction of curl depended on the physical state of the fibers, i.e. liberated or in wood matrix. In the pulping stage, the fiber continue to be supported by neighboring fibers, as the delignified chips maintain their form. However, in the subsequent oxygen stage the fibers enter in the form of pulp (liberated fibers), which makes them more susceptible to changes in fiber form.

  • 19.
    Esteves, Cláudia S. V. G.
    et al.
    RISE INNVENTIA AB, Drottning Kristinas Vag 61, S-11428 Stockholm, Sweden..
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Östlund, Sören
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics, Vehicle Engineering and Solid Mechanics, Solid Mechanics.
    Brännvall, Elisabet
    RISE INNVENTIA AB, Drottning Kristinas Vag 61, S-11428 Stockholm, Sweden..
    Differences and similarities between kraft and oxygen delignification of softwood fibers: effects on mechanical properties2021In: Cellulose, ISSN 0969-0239, E-ISSN 1572-882X, Vol. 28, no 6, p. 3775-3788Article in journal (Refereed)
    Abstract [en]

    Charged groups in pulp have been shown to enhance the tensile strength of the paper produced from the pulp. Oxygen delignification introduces charged groups and it is of interest to determine how the delignification should be distributed between the cooking and the oxygen stage with respect to mechanical properties. A number of unbleached kraft cooked and oxygen delignified pulps within a wide kappa number range were produced and refined, and the effects of the refining on the morphology and mechanical properties were studied. The WRV correlated with the fiber charge and at a given fiber charge, kraft cooked and oxygen delignified pulps had the same WRV development in refining, although they had significantly different kappa numbers. The tensile strength development during refining depends on the fiber rigidity which is affected by the lignin content, the fiber charge and the chemical and mechanical processes used. Refining increased the curl of the kraft cooked pulps and decreased the curl of oxygen delignified pulps, irrespective of kappa number. A greater increase in tensile strength was seen for the pulps with a higher fiber charge and WRV, probably because of the greater degree of fibrillation achieved in the beating process. Despite the greater fiber deformation in the oxygen delignified pulps, the strength can be increased by a larger amount of charged groups and a greater swelling of the fibers.

  • 20.
    Esteves, Cláudia V. G.
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. RISE Research Institutes of Sweden, Bioeconomy and Health, Pulp, Paper and Packaging , Drottning Kristinas väg 61 , Stockholm , Sweden.
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology.
    Östlund, Sören
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics, Vehicle Engineering and Solid Mechanics, Solid Mechanics.
    Brännvall, Elisabet
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Engineering Pedagogics. RISE Research Institutes of Sweden , Bioeconomy and Health, Pulp, Paper and Packaging , Drottning Kristinas väg 61 , Stockholm , Sweden.
    The impact of bleaching on the yield of softwood kraft pulps obtained by high alkali impregnation2022In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 0, no 0Article in journal (Refereed)
    Abstract [en]

    High alkali impregnation (HAI) increases the total yield of softwood pulps following kraft cooking. This yield improvement is also maintained after oxygen delignification. This study evaluates how bleaching with either chlorine dioxide or hydrogen peroxide affects the final yield of samples obtained with standard and HAI. The chemical composition, viscosity, brightness, mechanical and morphological properties were studied. Compared to cooking after standard impregnation the yield improvement achieved by HAI was preserved in both types of bleaching sequences (2% units for chlorine dioxide and 4% units for hydrogen peroxide). The introduction of charged groups into the cellulose fibers was higher with hydrogen peroxide bleaching than with chlorine dioxide however, no significant impact was seen on the swelling or mechanical properties. The brightness was higher for the pulps bleached with chlorine dioxide compared with hydrogen peroxide. Hydrogen peroxide bleaching resulted in similar brightness development for both standard and HAI. Fibers bleached with chlorine dioxide had the highest curl index (16-17%) compared to the fibers bleached with hydrogen peroxide (15%). 

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  • 21. Galysh, V.
    et al.
    Sevastyanova, Olena
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Deartel, M.
    Lindström, Mikael E.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Gornikov, Yu.
    Impact of ferrocyanide salts on the thermo-oxidative degradation of lignocellulosic sorbents2017In: Journal of thermal analysis and calorimetry (Print), ISSN 1388-6150, E-ISSN 1588-2926, Vol. 128, no 2, p. 1019-1025Article in journal (Refereed)
    Abstract [en]

    The catalytic effect of ferrocyanide salts of d-metals on the thermo-oxidative degradation of lignocellulose-inorganic sorbents derived from apricot seed shells was investigated by differential thermal analysis. A comparative analysis of the thermal characteristics of the apricot seed shells and the lignocellulose matrix obtained from the shells by alkali-acid pretreatment was performed. It was shown that acid-alkali pretreatment of the apricot seed shells increases the thermal stability of the lignocellulosic material, due to the removal of low molecular weight carbohydrates and other components. The thermal degradation process of the lignocellulose-inorganic samples containing different ferrocyanides occurred at lower temperatures than the initial lignocellulose matrix, indicating the catalytic activity of modifiers. It was demonstrated that for the sorbents containing mixed salts of potassium cobalt and potassium nickel ferrocyanide, thermal destruction ends at temperatures that are 60 A degrees C lower than those for the initial lignocellulose matrix. The obtained results also show that the thermal destruction of composite lignocellulose-inorganic sorbents can be a suitable method for their disposal.

  • 22.
    Gawdzik, Barbara
    et al.
    Marie Curie Sklodowska Univ, Dept Polymer Chem, PL-20614 Lublin, Poland..
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Special Issue: "Environmentally Friendly Polymeric Blends from Renewable Sources"2021In: Materials, ISSN 1996-1944, E-ISSN 1996-1944, Vol. 14, no 17, article id 4858Article in journal (Other academic)
  • 23. Gioia, C.
    et al.
    Colonna, M.
    Tagami, Ayumu
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. Nippon Paper Industries Co., Ltd., Research Laboratory, Oji, Kita-ku, Tokyo, 114-0002, Japan.
    Medina, Lilian
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Berglund, Lars
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Lawoko, Martin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Lignin-Based Epoxy Resins: Unravelling the Relationship between Structure and Material Properties2020In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 21, no 5, p. 1920-1928Article in journal (Refereed)
    Abstract [en]

    Here we investigate the relationship between thermomechanical properties and chemical structure of well-characterized lignin-based epoxy resins. For this purpose, technical lignins from eucalyptus and spruce, obtained from the Kraft process, were used. The choice of lignins was based on the expected differences in molecular structure. The lignins were then refined by solvent fractionation, and three fractions with comparable molecular weights were selected to reduce effects of molar mass on the properties of the final thermoset resins. Consequently, any differences in thermomechanical properties are expected to correlate with molecular structure differences between the lignins. Oxirane moieties were selectively introduced to the refined fractions, and the resulting lignin epoxides were subsequently cross-linked with two commercially available polyether diamines (Mn = 2000 and 400) to obtain lignin-based epoxy resins. Molecular-scale characterization of the refined lignins and their derivatives were performed by 31P NMR, 2D-NMR, and DSC methods to obtain the detailed chemical structure of original and derivatized lignins. The thermosets were studied by DSC, DMA, and tensile tests and demonstrated diverse thermomechanical properties attributed to structural components in lignin and selected amine cross-linker. An epoxy resin with a lignin content of 66% showed a Tg of 79 °C from DMA, Young's modulus of 1.7 GPa, tensile strength of 66 MPa, and strain to failure of 8%. The effect of molecular lignin structure on thermomechanical properties was analyzed, finding significant differences between the rigid guaiacyl units in spruce lignin compared with sinapyl units in eucalyptus lignin. The methodology points toward rational design of molecularly tailored lignin-based thermosets.

  • 24.
    Giummarella, Nicola
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology.
    Pylypchuk, Ievgen, V
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology.
    Lawoko, Martin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    New Structures in Eucalyptus Kraft Lignin with Complex Mechanistic Implications2020In: ACS Sustainable Chemistry and Engineering, E-ISSN 2168-0485, Vol. 8, no 29, p. 10983-10994Article in journal (Refereed)
    Abstract [en]

    Recent years have seen the development of technically feasible methods to retrieve kraft lignin from the black liquor as solids or liquids. This opens enormous opportunities to position kraft lignin as a renewable aromatic polymer precursor. However, the heterogeneity of kraft lignin is one major hurdle and manifests in its largely unknown molecular structure, which in recent years has drawn further attention. In this context, we herein studied the detailed structure of Eucalyptus kraft lignin with special emphasis on identifying new linkages signatory to retro-aldol and subsequent radical coupling reactions, which we recently showed to be a key reaction sequence contributing to the structure of spruce kraft lignin. In combination with novel model studies, we unequivocally identified new structures by advanced 2D NMR characterization of Eucalyptus kraft lignin, i.e., 3,5-tetramethoxy-para-diphenol, 3-dimethoxy-para-diphenol and small amounts of 3,5-dimethoxy-benzoquinone. These structures are signatory to retro-aldol followed by radical coupling reactions. The two diphenol structures were further quantified by 1D C-13 NMR at 9% of the interunit linkages in Eucalyptus kraft lignin, which was comparable to the amounts we previously identified in softwood kraft lignin (10%). Radical condensation of kraft lignin to form carbon-carbon bonds therefore does not discriminate between syringyl lignin and guaiacyl lignin units. We rationalize such indiscrimination to emanate from possibilities for radical couplings at unsubstituted C-1 in the formed syringol and guaiacol lignin as a result of the retro-aldol reaction.

  • 25.
    Goliszek, M.
    et al.
    Marie Curie Sklodowska Univ, Fac Chem, Maria Curie Sklodowska Sq 3, PL-20031 Lublin, Poland..
    Podkoscielna, B.
    Marie Curie Sklodowska Univ, Fac Chem, Maria Curie Sklodowska Sq 3, PL-20031 Lublin, Poland..
    Fila, K.
    Marie Curie Sklodowska Univ, Fac Chem, Maria Curie Sklodowska Sq 3, PL-20031 Lublin, Poland..
    Riazanova, Anastasia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Aminzadeh, Selda
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Sevastyanova, O.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Gun'ko, V. M.
    Chuiko Inst Surface Chem, 17 Gen Naumov Str, UA-03164 Kiev, Ukraine..
    Synthesis and structure characterization of polymeric nanoporous microspheres with lignin2018In: Cellulose, ISSN 0969-0239, E-ISSN 1572-882X, Vol. 25, no 10, p. 5843-5862Article in journal (Refereed)
    Abstract [en]

    Nanoporous microspheres with divinylbenzene (DVB), styrene (St), and lignin were synthesized by an emulsion-suspension polymerization method. Several types of lignins were used: (1) kraft lignin before (L-unmod) and after modification with methacryloyl chloride (L-Met) and (2) low-molecular-weight kraft lignin unmodified (LWL-unmod) and modified with methacrylic anhydride (LWL-Met). LWL was prepared by ultrafiltration of industrial black liquor using a ceramic membrane with a molecular weight (Mw) cut-off of 5 kDa. The synthesis was optimized by addition of different amounts of lignins. The microsphere texture was characterized using low-temperature nitrogen adsorption and small angle X-ray scattering analyses. The microspheres were nano- and mesoporous with a specific surface area in the range of 0.1-409 m(2)/g. The morphology of the copolymers was studied using field emission scanning electron microscopy and atomic force microscopy. The thermal properties were studied using differential scanning calorimetry and thermogravimetric analysis methods. A significant difference in the microsphere roughness is affected by lignins due to the presence of lignin nanoparticles at the surface of the microspheres. Molecular modeling was used to predict the sorption properties of the copolymers affected by various fields around the particles. The particle size, polydispersity and zeta potential of the St + DVB, L-Met + St + DVB and L-unmod + St + DVB samples were measured by dynamic light scattering. Additionally, the point of zero charge of the samples was determined using potentiometric titration. The materials studied have a great potential for sorption processes due to their developed porosity and the presence of a number of active surface functionalities. [GRAPHICS] .

  • 26.
    Goliszek, M.
    et al.
    Marie Curie Sklodowska Univ, Dept Polymer Chem, M Curie Sklodowska Sq 5, PL-20031 Lublin, Poland..
    Podkoscielna, B.
    Marie Curie Sklodowska Univ, Dept Polymer Chem, M Curie Sklodowska Sq 5, PL-20031 Lublin, Poland..
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Fila, K.
    Marie Curie Sklodowska Univ, Dept Polymer Chem, M Curie Sklodowska Sq 5, PL-20031 Lublin, Poland..
    Chabros, A.
    Marie Curie Sklodowska Univ, Dept Polymer Chem, M Curie Sklodowska Sq 5, PL-20031 Lublin, Poland..
    Paczkowski, P.
    Marie Curie Sklodowska Univ, Dept Polymer Chem, M Curie Sklodowska Sq 5, PL-20031 Lublin, Poland..
    Investigation of accelerated aging of lignin-containing polymer materials2019In: International Journal of Biological Macromolecules, ISSN 0141-8130, E-ISSN 1879-0003, Vol. 123, p. 910-922Article in journal (Refereed)
    Abstract [en]

    This paper presents the results of an accelerated aging test of biocomposites containing kraft lignin, where the resistance of the materials against humidity and light exposure was investigated. Low molecular weight lignin, modified with methacrylic anhydride (LWL-Met), was copolymerized with two commercial monomers: styrene (St) and methyl methacrylate (MMA). The biocomposites were obtained by a bulk polymerization method using alpha,alpha'-azoiso-bis-butyronitrile (AIBN) as a free radical polymerization initiator. The Shore D hardness of the obtained materials was determined before and after aging test. The changes in the chemical structures of polymers, as the result of aging were analyzed by using the attenuated total reflection Fourier transform infrared (ATR/FT-IR) spectroscopy method. The thermal behavior and stability of the obtained materials were investigated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The surface topography was determined using the optical topography method to evaluate the changes on the surface of synthesized materials resulted from accelerated aging. Application of modified lignin as a biocomponent in the polymerization process and its influence on the properties of the obtained materials before and after the accelerated aging test are discussed.

  • 27.
    Goliszek, M.
    et al.
    Department of Polymer Chemistry, Faculty of Chemistry, Maria Curie-Sklodowska University, M. Curie-Sklodowska Sq. 3, Lublin, 20-031, Poland.
    Wiącek, A. E.
    Department of Interfacial Phenomena, Faculty of Chemistry, Maria Curie-Sklodowska University, M. Curie-Sklodowska Sq. 3, Lublin, 20-031, Poland.
    Wawrzkiewicz, M.
    Department of Inorganic Chemistry, Faculty of Chemistry, Maria Curie-Sklodowska University, M. Curie-Sklodowska Sq. 3, Lublin, 20-031, Poland.
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Podkościelna, B.
    Department of Polymer Chemistry, Faculty of Chemistry, Maria Curie-Sklodowska University, M. Curie-Sklodowska Sq. 3, Lublin, 20-031, Poland.
    The impact of lignin addition on the properties of hybrid microspheres based on trimethoxyvinylsilane and divinylbenzene2019In: European Polymer Journal, ISSN 0014-3057, E-ISSN 1873-1945, Vol. 120, article id 109200Article in journal (Refereed)
    Abstract [en]

    Hybrid microspheres of trimethoxyvinylsilane, divinylbenzene and lignin were synthesized by a suspension polymerization method. Commercially available alkali lignin and the methanol fraction of softwood kraft lignin were used as the bio-component of polymeric microspheres. The methanol fraction of lignin had a high content of phenolic groups and low molecular weight which are desirable features for further methacrylation. The physicochemical and electrokinetic properties of the synthesized materials were analyzed in detail. The preliminary modification of the hybrids with lignin had a noticeable positive effect on the stability and electrokinetic properties of the final products compared to those of unmodified microspheres composed of divinylbenzene and trimethoxyvinylsilane (DVB-TMVS). Thermal properties were investigated by differential scanning calorimetry and thermogravimetric analysis, and the morphology was studied using scanning electron microscopy. The microsphere texture was characterized using low-temperature nitrogen adsorption. The microspheres were mesoporous with a specific surface area in the range of 149–305 m2/g. The porosity of the hybrid materials was influenced by the type and modification of the lignin; microspheres with modified lignin in general had more developed porous structures. The applicability of the porous materials obtained as sorbents for the removal of dyes was confirmed in a batch experiment. The mechanism of interactions between dyes and a bio-sorbent containing lignin may involve electrostatic interactions between the positively charged nitrogen atoms of the dye molecule and the dissociated functional groups of the adsorbent, hydrogen bonding and π-π interactions.

  • 28.
    Goliszek, Marta
    et al.
    Marie Curie Sklodowska Univ, Inst Chem Sci, Dept Polymer Chem, Fac Chem, M Curie Sklodowska Sq 5, PL-20031 Lublin, Poland.;Marie Curie Sklodowska Univ, Inst Chem Sci, Analyt Lab, Fac Chem, M Curie Sklodowska Sq 5, PL-20031 Lublin, Poland..
    Kolodynska, Dorota
    Marie Curie Sklodowska Univ, Inst Chem Sci, Dept Inorgan Chem, Fac Chem, M Curie Sklodowska Sq 5, PL-20031 Lublin, Poland..
    Pylypchuk, Ievgen, V
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology.
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Podkoscielna, Beata
    Marie Curie Sklodowska Univ, Inst Chem Sci, Dept Polymer Chem, Fac Chem, M Curie Sklodowska Sq 5, PL-20031 Lublin, Poland..
    Synthesis of lignin-containing polymer hydrogels with tunable properties and their application in sorption of nickel(II) ions2021In: Industrial crops and products (Print), ISSN 0926-6690, E-ISSN 1872-633X, Vol. 164, article id 113354Article in journal (Refereed)
    Abstract [en]

    Polymer hydrogels with lignin in the form of microspheres have been synthesized and their properties were evaluated. Prior to the polymerization, hardwood lignin (Eucalyptus grandis) was modified with methacryloyl chloride, and unmodified lignin (L-N) and its methacrylic derivative (L-M) were polymerized with 2-hydroxyethyl methacrylate (HEMA) and divinylbenzene (DVB) in different ratios using suspension polymerization. The presence of characteristic functional groups in the synthesized hydrogels was confirmed using attenuated total reflectance Fourier transform infrared spectroscopy (ATR/FT-IR) and NMR. Thermal properties were determined by means of differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Swelling was studied in common organic solvents and distilled water. The shapes of the hydrogels were confirmed by scanning electron microscopy (SEM) and optical microscopy. The addition of lignin significantly increased the swelling ability of the hydrogels in water and acetone. The incorporation of methacrylated lignin into the structure of HEMA-DVB hydrogels increased their sorption of Ni(II) ions by 30 % showing that these hydrogels are a promising material for use in nickel removal and recovery, as well as contributing to a better utilization of lignin.

  • 29.
    Goliszek, Marta
    et al.
    Marie Curie Sklodowska Univ, Fac Chem, Inst Chem Sci, Dept Polymer Chem, M Curie Sklodowska Sq 5, PL-20031 Lublin, Poland.;Marie Curie Sklodowska Univ, Fac Chem, Inst Chem Sci, Analyt Lab, M Curie Sklodowska Sq 5, PL-20031 Lublin, Poland..
    Podkoscielna, Beata
    Marie Curie Sklodowska Univ, Fac Chem, Inst Chem Sci, Dept Polymer Chem, M Curie Sklodowska Sq 5, PL-20031 Lublin, Poland..
    Klepka, Tomasz
    Lublin Univ Technol, Fac Mech Engn, Dept Technol & Polymer Proc, Nadbystrzycka 36, PL-20618 Lublin, Poland..
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Preparation, Thermal, and Mechanical Characterization of UV-Cured Polymer Biocomposites with Lignin2020In: Polymers, E-ISSN 2073-4360, Vol. 12, no 5Article in journal (Refereed)
    Abstract [en]

    The preparation and the thermal and mechanical characteristics of lignin-containing polymer biocomposites were studied. Bisphenol A glycerolate (1 glycerol/phenol) diacrylate (BPA.GDA) was used as the main monomer, and butyl acrylate (BA), 2-ethylhexyl acrylate (EHA) or styrene (St) was used as the reactive diluent. Unmodified lignin (L) or lignin modified with methacryloyl chloride (L-M) was applied as an ecofriendly component. The influences of the lignin, its modification, and of the type of reactive diluent on the properties of the composites were investigated. In the biocomposites with unmodified lignin, the lignin mainly acted as a filler, and it seemed that interactions occurred between the hydroxyl groups of the lignin and the carbonyl groups of the acrylates. When methacrylated lignin was applied, it seemed to take part in the creation of a polymer network. When styrene was added as a reactive diluent, the biocomposites had a more homogeneous structure, and their thermal resistance was higher than those with acrylate monomers. The use of lignin and its methacrylic derivative as a component in polymer composites promotes sustainability in the plastics industry and can have a positive influence on environmental problems related to waste generation.

  • 30.
    Goliszek, Marta
    et al.
    Marie Curie Sklodowska Univ, Fac Chem, Dept Polymer Chem, M Curie Sklodowska Sq 3, PL-20031 Lublin, Poland..
    Podkoscielna, Beata
    Marie Curie Sklodowska Univ, Fac Chem, Dept Polymer Chem, M Curie Sklodowska Sq 3, PL-20031 Lublin, Poland..
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Gawdzik, Barbara
    Marie Curie Sklodowska Univ, Fac Chem, Dept Polymer Chem, M Curie Sklodowska Sq 3, PL-20031 Lublin, Poland..
    Chabros, Artur
    Marie Curie Sklodowska Univ, Fac Chem, Dept Polymer Chem, M Curie Sklodowska Sq 3, PL-20031 Lublin, Poland..
    The Influence of Lignin Diversity on the Structural and Thermal Properties of Polymeric Microspheres Derived from Lignin, Styrene, and/or Divinylbenzene2019In: Materials, ISSN 1996-1944, E-ISSN 1996-1944, Vol. 12, no 18, article id 2847Article in journal (Refereed)
    Abstract [en]

    This work investigates the impact of lignin origin and structural characteristics, such as molecular weight and functionality, on the properties of corresponding porous biopolymeric microspheres obtained through suspension-emulsion polymerization of lignin with styrene (St) and/or divinylbenzene (DVB). Two types of kraft lignin, which are softwood (Picea abies L.) and hardwood (Eucalyptus grandis), fractionated by common industrial solvents, and related methacrylates, were used in the synthesis. The presence of the appropriate functional groups in the lignins and in the corresponding microspheres were investigated by attenuated total reflectance Fourier transform infrared spectroscopy (ATR/FT-IR), while the thermal properties were studied by differential scanning calorimetry (DSC). The texture of the microspheres was characterized using low-temperature nitrogen adsorption. The swelling studies were performed in typical organic solvents and distilled water. The shapes of the microspheres were confirmed with an optical microscope. The introduction of lignin into a St and/or DVB polymeric system made it possible to obtain highly porous functionalized microspheres that increase their sorption potential. Lignin methacrylates created a polymer network with St and DVB, whereas the unmodified lignin acted mainly as an eco-friendly filler in the pores of St-DVB or DVB microspheres. The incorporation of biopolymer into the microspheres could be a promising alternative to a modification of synthetic materials and a better utilization of lignin.

  • 31. Gordobil, O.
    et al.
    Moriana, Rosana
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology.
    Zhang, Liming
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology.
    Labidi, J.
    Sevastyanova, Olena
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Assesment of technical lignins for uses in biofuels and biomaterials: Structure-related properties, proximate analysis and chemical modification2016In: Industrial crops and products (Print), ISSN 0926-6690, E-ISSN 1872-633X, Vol. 83, p. 155-165Article in journal (Refereed)
    Abstract [en]

    The potential of organosolv and kraft eucalyptus and spruce lignin as feedstock for polymeric materials and biofuel applications was assessed. Proximate analysis was used to predict the heating values and char formation. Chemical modification, based on the esterification reaction with methacryloyl chloride, was applied to introduce vinyl groups into the lignin macromolecules for enhanced reactivity. Kraft eucalyptus and spruce lignins had a more condensed structure than organosolv lignins, which resulted in greater thermal stability for these lignins. For different species within the same process, the thermal parameters showed a correlation with certain structural and compositional parameters (ash and sugars content, molecular weight and degree of condensation). Organosolv spruce lignin produced the highest heating value of 24. MJ/Kg, which is suitable for biofuel applications. The content of phenolic OH groups was higher for kraft lignins and especially higher for softwood lignins, both organosolv and kraft. The degree of methacrylation, estimated from the content of vinyl groups per C9 lignin unit, was significantly greater for organosolv lignins than for kraft lignins despite the higher OH-groups content in the latter.

  • 32.
    Gordobil, Oihana
    et al.
    InnoRenew CoE, Livade 6, Izola 6310, Slovenia..
    Li, Huisi
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Izquierdo, Ana Ayerdi
    TECNALIA, Basque Res & Technol Alliance BRTA, Mikeletegi Pasealekua 2, San Sebastian 20009, Spain..
    Egizabal, Ainhoa
    TECNALIA, Basque Res & Technol Alliance BRTA, Mikeletegi Pasealekua 2, San Sebastian 20009, Spain..
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology.
    Sandak, Anna
    InnoRenew CoE, Livade 6, Izola 6310, Slovenia.;Univ Primorska, Fac Math Nat Sci & Informat Technol, Glagoljaska 8, Koper 6000, Slovenia..
    Surface chemistry and bioactivity of colloidal particles from industrial kraft lignins2022In: International Journal of Biological Macromolecules, ISSN 0141-8130, E-ISSN 1879-0003, Vol. 220, p. 1444-1453Article in journal (Refereed)
    Abstract [en]

    The morphology control of lignin through particle size reduction to nanoscale seems to be a suitable conversion technology to overcome the intrinsic limitations of its native form to develop a wide range of biomaterials with high performance. Colloidal lignin particles (CLPs) in the range of 150-200 nm were synthesised from hardwood and softwood kraft lignins by the solvent shifting method. The initial molecular features of kraft lignins were evaluated in terms of purity, molecular weight distribution, and chemical functionalities. The impact of the lignin source and structure on the morphology, size distribution, and surface chemistry of CLPs was evaluated by particle size analyser, SEM, TEM and H-1 NMR. The results evidenced the influence of the botanical origin on the morphology and surface chemistry of particles. Furthermore, the antioxidant properties and cytotoxicity of lignins and corresponding CLPs, towards lung fibroblast cells were compared. CLPs from hardwood kraft lignins exhibited higher antioxidant power against DPPH free radical and a higher cytotoxic effect (IC30 = 67-70 mu g/mL) against lung fibroblast when compared to CLPs from softwood kraft lignin (IC30 = similar to 91 mu g/mL). However, the cytotoxicity of these biomaterials was dose-dependent, suggesting their potential application as active ingredients in cosmetic and pharmaceutic products at low concentrations.

  • 33. Halysh, V.
    et al.
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Pikus, S.
    Dobele, G.
    Pasalskiy, B.
    Gun´ko, V. M.
    Kartel, M.
    Sugarcane bagasse and straw as low-cost lignocellulosic sorbents for the removal of dyes and metal ions from water2020In: Cellulose, ISSN 0969-0239, E-ISSN 1572-882X, Vol. 27, no 14, p. 8181-8197Article in journal (Refereed)
    Abstract [en]

    Abstract: Sugarcane bagasse (stalk) and straw (leaves), an agricultural waste, which had been subjected to either an organosolv or organosolv-oxidative pretreatment were used for the removal of methylene blue dye or heavy metals (Fe(III) and Cu(II)) from model aqueous solutions. The sorption of methylene blue was investigated as a function of pH, dye concentration, and contact time. The sorption of metal ions was studied as a function of concentration. Classical Langmuir and Freundlich adsorption models were used to analyze the sorption process. It was shown that adsorption isotherms fitted better into Freundlich isotherm model, which assumes a multilayer adsorption on a heterogeneous surface. The morphological, textural, and structural characteristics such as bulk and true densities, particle size distributions, porosity, and thermal decomposition features of the biosorbents were determined to understand better the mechanism of sorption of various pollutants. The results showed significant differences in the chemical compositions and physical properties of the initial and modified biomass samples, especially for the cellulosic biosorbents prepared with organosolv-oxidative pretreatment. For the removal of dyes, the development of a pore structure as a result of the pretreatment seemed to play an important role, while the sorption of metals was strongly dependent on the chemical composition of the biosorbent. The highest adsorption capacity for methylene blue and for Fe(III) and Cu(II) was obtained for a lignocellulosic sorbent from sugarcane straw prepared by organosolv pretreatment. The results obtained confirm a great potential use of agricultural waste from sugarcane industry in wastewater treatment. 

  • 34.
    Halysh, Vita
    et al.
    Igor Sikorsky Kyiv Polytech Inst, Peremogy Ave 37-4, UA-03056 Kiev, Ukraine.;Natl Acad Sci Ukraine, OO Chuiko Inst Surface Chem, Gen Naumov Str 17, UA-03164 Kiev, Ukraine..
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    de Carvalho, Danila Morais
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Riazanova, Anastasiia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Lindström, Mikael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Gomelya, Mykola
    Igor Sikorsky Kyiv Polytech Inst, Peremogy Ave 37-4, UA-03056 Kiev, Ukraine..
    Effect of oxidative treatment on composition and properties of sorbents prepared from sugarcane residues2019In: Industrial crops and products (Print), ISSN 0926-6690, E-ISSN 1872-633X, Vol. 139, article id UNSP 111566Article in journal (Refereed)
    Abstract [en]

    Efficient sorbents for the removal of cationic dye were prepared from sugarcane bagasse (stalk) and straw (leaves) by oxidative pre-treatment with hydrogen peroxide (H2O2) in acetic acid. The effects of variables, such as concentration of H2O2, temperature and time on the properties of the fiber sorbents obtained were studied according to a 2(3) full-factorial design. For comparison, an oxidative treatment of sugarcane biomass with glacial acetic acid was also used. The yields of the materials obtained and their chemical composition were characterized and compared. Fourier transform infrared spectroscopy, field-emission scanning electron microscopy and benzene vapor adsorption were used to investigate the structural properties and morphology of the initial materials and sorbents. The sorption of methylene blue dye was used to assess the efficiency of dye removal by the sorbents. The pre-treatment conditions significantly affected the sorbent yield, their chemical composition (contents of cellulose, lignin and ash) as well as their sorption properties. The cellulosic sorbent (C-sorbent) from sugarcane bagasse obtained by pre-treatment with H2O2 in acetic acid and the lignocellulosic sorbent (LC-sorbent) from sugarcane straw obtained by pre-treatment with glacial acetic acid, had the highest sorption capacity for the methylene blue dye. For both types of sorbents, the sorption capacity increased with chemical pretreatment as a result of an increase in pore volume.

  • 35.
    Halysh, Vita
    et al.
    Igor Sikorsky Kyiv Polytech Inst, Fac Chem Engn, Dept Ecol & Technol Plant Polymers, Peremogy Avenu 37-4, UA-03056 Kiev, Ukraine.;Natl Acad Sci Ukraine, OO Chuiko Inst Surface Chem, Gen Naumov Str 17, UA-03164 Kiev, Ukraine..
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Riazanova, Anastasia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Pasalskiy, Bogdan
    Kyiv Natl Univ Trade & Econ, Kyoto Str 19, UA-02156 Kiev, Ukraine..
    Budnyak, Tetyana
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. Natl Acad Sci Ukraine, OO Chuiko Inst Surface Chem, Gen Naumov Str 17, UA-03164 Kiev, Ukraine..
    Lindström, Mikael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Kartel, Mykola
    Natl Acad Sci Ukraine, OO Chuiko Inst Surface Chem, Gen Naumov Str 17, UA-03164 Kiev, Ukraine..
    Walnut shells as a potential low-cost lignocellulosic sorbent for dyes and metal ions2018In: Cellulose, ISSN 0969-0239, E-ISSN 1572-882X, Vol. 25, no 8, p. 4729-4742Article in journal (Refereed)
    Abstract [en]

    Currently, it is necessary to develop new methods and materials for solving the problem of environmental pollution by various toxicants. For these purposes, vegetal materials can be used. In this study, efficient low-cost sorbents based on walnut shells, an agro-industrial by-product, were prepared by treatment with acetic acid or a mixture of acetic acid and hydrogen peroxide. It was shown that the treatments significantly affected the composition and structure of walnut shells and their sorption properties with respect to organic dyes (methylene blue, methyl violet, and murexide) and heavy metal ions. Methylene blue dye was used for additional studies on the effect of pH, contact time and kinetics of sorption. The maximum adsorption rate of the dye occurred within the first 30 min of contact, during which the concentration of methylene blue in the solution was reduced by more than half. Full sorption equilibrium was reached within 180-230 min for studied samples. The adsorption kinetics of methylene blue was found to best be described by pseudo-second-order kinetic model. It was shown that dyes adsorption processes were well described by Freundlich model, which takes into consideration the heterogeneity of the surface of the adsorbent. The obtained plant sorbents are characterized by a high sorption capacity for heavy metal ions (18-29 mg/g for Fe3+ and 33-44 mg/g for Cu-2). Due to their numerous advantages, such as the high sorption capacity, high availability and low cost of raw materials, simplicity of disposal and nontoxicity, the obtained natural sorbents may have a wide practical use in industrial wastewater treatment. [GRAPHICS] .

  • 36.
    Han, Tong
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    Sophonrat, Nanta
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering.
    Tagami, Ayumu
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Mellin, P.
    Yang, Weihong
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Energy and Furnace Technology.
    Characterization of lignin at pre-pyrolysis temperature to investigate its melting problem2019In: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 235, p. 1061-1069Article in journal (Refereed)
    Abstract [en]

    Technical lignin particles melt under relatively low temperature. This results in the problem in the continuous feeding and fluidization during lignin pyrolysis, which in turn limits its utilization on a large scale. In this study, two most available types of lignin have been used to investigate the lignin melting problem, which are Kraft lignin (KL) from pulping process and hydrolysis lignin (HL) from bio-ethanol production process. Elemental composition, thermal property and thermally decomposed derivatives of each sample are tested by elemental analyzer, TGA, DSC, and Py-GC/MS. Morphology, structure and crystal change before and after heat treatment are tested by microscopy, FTIR and XRD. All results suggest that lignin structure determines its melting properties. Kraft lignin from pulping process contains a less cross-linked structure. It melts under heating. On the other hand, hydrolysis lignin from hydrolysis process contains a highly crossed-linked and condensed structure. It does not melt before decomposition under heat treatment. Modifying lignin structure is suggested for the resolution of technical lignin melting problem.

  • 37. Lange, H.
    et al.
    Schiffels, P.
    Sette, M.
    Sevastyanova, Olena
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Crestini, C.
    Fractional Precipitation of Wheat Straw Organosolv Lignin: Macroscopic Properties and Structural Insights2016In: ACS Sustainable Chemistry and Engineering, E-ISSN 2168-0485, Vol. 4, no 10, p. 5136-5151Article in journal (Refereed)
    Abstract [en]

    Wheat straw organosolv lignin has been thoroughly characterized with respect to bulk material properties, surface properties, and structural characteristics by means of antioxidant assays and determination of the equilibrium constant in water-octanol partitioning, i.e., logP determination, optimized gel permeation chromatography, quantitative 31P NMR spectroscopy, quantitative HSQC measurements, and XPS studies. The material was subsequently fractionally precipitated based on a binary solvent system comprised of n-hexane and acetone to yield four fractions that exhibit distinct molecular mass characteristics, while displaying similar structural characteristics, as revealed by the same set of analysis techniques applied to them. Extensive correlation studies underline the versatility of the obtained fractions as higher quality starting materials for lignin valorization approaches since, for example, glass transition temperatures correlate well with number-average molecular weights, applying the Flory-Fox relation as well as its Ogawa and Loshaek variations.

  • 38.
    Lange, Heiko
    et al.
    Univ Roma Tor Vergata, Dept Chem Sci & Technol, Rome, Italy..
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Crestini, Claudia
    Univ Roma Tor Vergata, Dept Chem Sci & Technol, Rome, Italy..
    Correlating structural features of lignin with physical properties: Toward a descriptive-predictive database2015In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 249Article in journal (Other academic)
  • 39. Lauberts, Maris
    et al.
    Sevastyanova, Olena
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Ponomarenko, Jevgenija
    Dizhbite, Tatjana
    Dobele, Galina
    Volperts, Alexandr
    Lauberte, Liga
    Telysheva, Galina
    Fractionation of technical lignin with ionic liquids as a method for improving purity and antioxidant activity2017In: INDUSTRIAL CROPS AND PRODUCTS, ISSN 0926-6690, Vol. 95, p. 512-520Article in journal (Refereed)
    Abstract [en]

    Alder soda lignin, a by-product of the chemical processing of black alder wood, was fractionated using ionic liquids (ILs) based on the 1-buthyl-3-methylimidazolium [Bmim] cation and the following anions: chloride ([Bmim]Cl), dimethylphosphate ([Bmim]Me2PO4), acetate ([Brhim]OAc) and tosylate ([Bmim]OTs). The aim was to obtain lignin fractions of improved purity for further application as antioxidants. The purity and properties of the IL lignin fractions were compared with those of other lignin fractions obtained using sequential extraction with organic solvents. The original lignin and the lignin fractions were characterized by analytical pyrolysis (Py-GC/MS/FID), size-permeation chromatography (GPC), electron paramagnetic resonance (EPR) spectroscopy and wet chemistry methods. The lignin treatment with [Bmim]DMP, [Bmim]OAc and [Bmim]OTs produced fractions with a lignin content of 98-99%. These fractions along with the n-propanol and methanol fractions obtained using sequential organic solvent extraction were enriched with certain structural features that had a positive impact on lignin antioxidant activity, according to the results from DPPH center dot and ORAC assays.

  • 40.
    Li, Dongfang
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology.
    Sevastyanova, Olena
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology.
    Ek, Monica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology.
    Ionic Liquids pretreatment of cellulose fiber materials for improvement of reactivity and value added applications2011In: 16th International Symposium on Wood, Fiber and Pulping Chemistry - Proceedings, ISWFPC , 2011, p. 503-510Conference paper (Refereed)
    Abstract [en]

    Cellulose is one of the most abundant biological and renewable materials in the world. The application of cellulose is widely distributed among various industries such as fiber, paper, pharmaceutical, membrane, polymer and paint. However, the utilization of cellulose or cellulosic materials has not been developed entirely because of its poor solubility in common organic solvents. Ionic liquids (ILs) are relatively new family of solvents for dissolution of cellulose. They are organic salts containing cations and anions with low melting temperature, which make them suitable for the solubilization of cellulose. Moreover, ILs are non-volatile, non-toxic, non-flammable and thermally and chemically stable. Cellulose dissolved in ILs can be regenerated with anti-solvents as water, ethanol and acetone. In this study, the pretreatment of both hardwood and softwood dissolving pulps with two ILs ([C4mim+]CH3COO- and [C4mim+]Cl-) were performed. Furthermore, the impact of treating cellulose with ILs was also evaluated by using different analytical techniques, such as size exclusion chromatography (SEC), thermal gravimetric analysis (TGA) and scanning electron microscopy (SEM).

  • 41.
    Li, Dongfang
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology.
    Sevastyanova, Olena
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology.
    Ek, Monica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology.
    Pretreatment of softwood dissolving pulp with ionic liquids2012In: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 66, no 8, p. 935-943Article in journal (Refereed)
    Abstract [en]

    Few Scandinavian pulp mills produce dissolving pulps; however, the demand on textile fibers is increasing. This study investigates the chemical interaction of dissolving pulp with ionic liquids (ILs), where softwood and hardwood industrial dissolving pulps were pretreated with ILs 1-butyl-3-methyl-imidazolium acetate ([C(4)mim(+)]CH3COO-) and 1-butyl-3-methyl-imdazolium chloride ([C(4)mim(+)]Cl-). Time and temperature dependence of the dissolution process as well as the impact of the pretreatment on the molecular weight properties, thermal stability, morphology, and crystallinity of the cellulose were evaluated by means of size exclusion chromatography (SEC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), X-ray diffraction (XRD), and solid state nuclear magnetic resonance (NMR). It was shown that the dissolution of cellulosic material in ILs is a temperature-dependent process; however, the viscosity of ILs affected the efficiency of dissolution at a given temperature. Molecular weight properties were affected negatively by increased dissolution temperature, while the type of antisolvent for the regeneration had no major impact on the degree of polymerization of cellulose. Water was more efficient than ethanol for the regeneration of cellulose when performed at an elevated temperature. The pretreatment decreased the crystallinity of cellulosic material. This might lead to the increased accessibility and reactivity of cellulose.

  • 42.
    Li, Huisi
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Kulachenko, Artem
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics, Vehicle Engineering and Solid Mechanics, Solid Mechanics.
    Mathew, Aji P.
    Stockholm Univ, Div Mat & Environm Chem, SE-10691 Stockholm, Sweden..
    Stoltz, Raquel Bohn
    Valmet AB, Fiber Proc Business Unit, SE-65115 Karlstad, Sweden..
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology.
    Enhancing the Strength and Flexibility of Microfibrillated Cellulose Films from Lignin-Rich Kraft Pulp2023In: ACS Sustainable Chemistry and Engineering, E-ISSN 2168-0485, Vol. 11, no 47, p. 16793-16805Article in journal (Refereed)
    Abstract [en]

    Recent progress in nanocellulose production favors lignin-rich raw fibers due to their cost effectiveness, higher yield of unbleached pulp, and added benefits from residual lignin, positioning them as ideal substitutes for fossil-based materials in composites and packaging. Nonetheless, their application has been impeded due to their inferior mechanical properties. This study introduces a simplified method to enhance the strength of lignin-containing microfibrillated cellulose (LMFC) films using water as a plasticizer during drying. Both LMFC from unbleached pulps and lignin-free microfibrillated cellulose (MFC) from fully bleached industrial kraft pulp were prepared through an environmentally friendly and scalable method. Given the charged carboxylic groups from hemicellulose and residual lignin, the LMFC gel demonstrated greater colloidal stability compared to MFC. Moreover, lignin-rich films displayed heightened hydrophobicity and exceptional thermal stability (T-max > 345 degrees C). A significant improvement in tensile strength and Young's modulus of LMFC films was achieved with an elevated drying temperature from 40 degrees C to above 90 degrees C, increasing tensile strength from 248 to 283 MPa and Young's modulus by 84%. These improvements are attributed to the thermoplastic nature of lignin and the plasticizing effect of water at elevated temperatures. The longer fibers in microfibrillated films also improved the resistance to cracking in a folded state. The study highlights that enhancement of the properties of lignin-rich films can occur during the film making step itself, hinting at a sustainable, innovative method for creating robust and scalable materials for flexible devices, biocomposites, and packaging.

  • 43.
    Li, Jiebing
    et al.
    KTH, Superseded Departments (pre-2005), Fibre and Polymer Technology.
    Sevastyanova, Olena
    KTH, Superseded Departments (pre-2005), Fibre and Polymer Technology.
    Gellerstedt, Göran
    KTH, Superseded Departments (pre-2005), Fibre and Polymer Technology.
    The distribution of oxidizable structures in ECF- and TCF- bleached kraft pulps2002In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 17, no 4, p. 415-419Article in journal (Refereed)
    Abstract [en]

    The kappa number in kraft pulp contains contributions from lignin and from other oxidizable structures denoted as false lignin. The latter can be divided in hexenuronic acid groups and "non-lignin" structures. In this paper, the kappa number units due to the various contributing structures have been quantified by fractionation of the kappa number. Bleached spruce and birch kraft industrial pulps taken after each stage in an ECF (ODEQP) and in a TCF (OQOPQPO) bleaching sequence respectively have been assessed. Possible correlations between the content of false lignin, the pulp origin, the bleaching conditions, and brightness and viscosity values have been sought. It is concluded that the false lignin structures are formed predominantly during the cooking and oxygen delignification stages. The false lignin structures were found to give different responses in the various bleaching stages, but to have no influence on either pulp brightness or viscosity.

  • 44.
    Li, Jiebing
    et al.
    KTH, Superseded Departments (pre-2005), Fibre and Polymer Technology.
    Sevastyanova, Olena
    KTH, Superseded Departments (pre-2005), Fibre and Polymer Technology.
    Gellerstedt, Göran
    KTH, Superseded Departments (pre-2005), Fibre and Polymer Technology.
    The relationship between kappa number and oxidizable structures in bleached kraft pulps2002In: Journal of Pulp and Paper Science (JPPS), ISSN 0826-6220, Vol. 28, no 8, p. 262-266Article in journal (Refereed)
    Abstract [en]

    The relationship between residual oxidized lignin structures in spruce and birch kraft pulps and their kappa number contribution after each stage in an ODEQP (spruce) and an OQ(OP)Q(PO) (birch) sequence, respectively, has been investigated. Analysis by a modified kappa number method (OxDem kappa number) as well as by determination of permanganate oxidation equivalents on various isolated residual lignin samples revealed that the relationship between the lignin content and kappa number gradually changes as the bleaching sequence proceeds, giving values that differ substantially from that found in unbleached kraft pulp. These effects can be attributed to the successive oxidative fragmentation of aromatic rings and the formation of carboxyl and non-aromatic unsaturated structures in the residual lignin structure. Therefore, a kappa number determination on pulp which has been subjected to an oxidative stage will result in an underestimation of the lignin content.

  • 45.
    Mattsson, Tuve
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Azhar, Shoaib
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Bylin, Susanne
    Helander, Mikaela
    KTH.
    Henriksson, Gunnar
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Jedvert, K
    Lawoko, Martin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Lindström, Mikael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    McKee, Lauren S.
    KTH.
    Oinonen, Petri
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Westerberg, N
    Theliander, H
    Towards a wood based material biorefinery - A demonstrator2015In: 6th Nordic Wood Biorefinery Conference, NWBC 2015, VTT Technical Research Centre of Finland , 2015, p. 92-101Conference paper (Refereed)
    Abstract [en]

    Wood, the most abundant ligno-cellulosic raw material available, is a key potential feedstock for production of more sustainable alternatives to fossil-based materials. However advances within the fields of extraction and treatment processes within what is often referred to as the biorefinery concept is essential to allow for such transition. In this study, several different methods for the extraction and separation of wood constituents have been combined in a single process with the purpose of achieving a high overall efficiency of material extraction and utilisation. The work builds on several activities within the Wallenberg Wood Science Center (WWSC). The aim is to present a laboratory-scale demonstrator that illustrates how the different constituents can be separated from the wood matrix for later use in the production of bio-based materials and chemicals. The process steps involved have been tested as integral steps in a linked process for a scale of operations that range from the kilogram-scale down to the gram-scale. Industrially chipped softwood, containing mainly spruce with some pine, was used as raw material. 

  • 46. Mattsson, Tuve
    et al.
    Azhar, Shoaib
    KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Eriksson, Susanna
    Helander, Mikaela
    KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Henriksson, Gunnar
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Jedvert, Kerstin
    Lawoko, Martin
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Lindström, Mikael E.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    McKee, Lauren S.
    KTH, School of Biotechnology (BIO), Glycoscience. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Oinonen, Petri
    KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Sevastyanova, Olena
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Westerberg, Niklas
    Theliander, Hans
    The Development of a Wood-based Materials-biorefinery2017In: BioResources, ISSN 1930-2126, E-ISSN 1930-2126, Vol. 12, no 4, p. 9152-9182Article in journal (Refereed)
    Abstract [en]

    Several different methods for the extraction, separation, and purification of wood constituents were combined in this work as a unified process with the purpose of achieving a high overall efficiency of material extraction and utilization. This study aimed to present a laboratory-scale demonstrator biorefinery that illustrated how the different wood constituents could be separated from the wood matrix for later use in the production of new bio-based materials and chemicals by combining several approaches. This study builds on several publications and ongoing activities within the Wallenberg Wood Science Center (WWSC) in Sweden on the theme "From wood to material components." Combining the approaches developed in these WWSC projects - including mild steam explosion, membrane and chromatographic separation, enzymatic treatment and leaching, ionic liquid extraction, and fractionation together with Kraft pulping - formed an outline for a complete materials-biorefinery. The process steps involved were tested as integral steps in a linked process. The scale of operations ranged from the kilogram-scale to the gram-scale. The feasibility and efficiency of these process steps in a biorefinery system were assessed, based on the data, beginning with whole wood.

  • 47.
    Mkrtchyan, Satenik
    et al.
    Department of Chemistry, Faculty of Natural Sciences, Matej Bel University, Tajovského 40, 97401 Banská Bystrica, Slovakia, Tajovského 40.
    Shkoor, Mohanad
    Department of Chemistry and Earth Sciences, Qatar University, P.O. Box 2713, Doha, Qatar.
    Phanindrudu, Mandalaparthi
    Inorganic and Physical Chemistry Division, CSIR-Indian Institute of Chemical Technology, Uppal Road, Tarnaka, Hyderabad 500607, India, Uppal Road, Hyderabad Tarnaka.
    Medved′, Miroslav
    Department of Chemistry, Faculty of Natural Sciences, Matej Bel University, Tajovského 40, 97401 Banská Bystrica, Slovakia, Tajovského 40; Regional Centre of Advanced Technologies and Materials, Czech Advanced Technology and Research Institute, Palacky University Olomouc, Křížkovského 511/8, 77900 Olomouc, Czech Republic, Křížkovského 511/8.
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology.
    Iaroshenko, Viktor O.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. Department of Chemistry, Faculty of Natural Sciences, Matej Bel University, Tajovského 40, 97401 Banská Bystrica, Slovakia, Tajovského 40; Department of Chemistry, University of Helsinki, A.I. Virtasen aukio 1, 00014 Helsinki, Finland, A.I. Virtasen aukio 1; Department of Biology/Chemistry, Center for Cellular Nanoanalytics (CellNanOs), Universität Osnabrück, Barbarastr. 7, D-49076 Osnabrück, Germany, Barbarastr. 7.
    Mechanochemical Defluorinative Arylation of Trifluoroacetamides: An Entry to Aromatic Amides2023In: Journal of Organic Chemistry, ISSN 0022-3263, E-ISSN 1520-6904, Vol. 88, no 2, p. 863-870Article in journal (Refereed)
    Abstract [en]

    The amide bond is prominent in natural and synthetic organic molecules endowed with activity in various fields. Among a wide array of amide synthetic methods, substitution on a pre-existing (O)C-N moiety is an underexplored strategy for the synthesis of amides. In this work, we disclose a new protocol for the defluorinative arylation of aliphatic and aromatic trifluoroacetamides yielding aromatic amides. The mechanochemically induced reaction of either arylboronic acids, trimethoxyphenylsilanes, diaryliodonium salts, or dimethyl(phenyl)sulfonium salts with trifluoroacetamides affords substituted aromatic amides in good to excellent yields. These nickel-catalyzed reactions are enabled by C-CF3 bond activation using Dy2O3 as an additive. The current protocol provides versatile and scalable routes for accessing a wide variety of substituted aromatic amides. Moreover, the protocol described in this work overcomes the drawbacks and limitations in the previously reported methods.

  • 48.
    Morais de Carvalho, Danila
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Abad, Antonio Martinez
    KTH, School of Biotechnology (BIO), Glycoscience.
    Evtuguin, D. V.
    Colodette, J. L.
    Lindström, Mikael
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Vilaplana, Francisco
    KTH, School of Biotechnology (BIO), Glycoscience.
    Sevastyanova, Olena
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Isolation and characterization of acetylated glucuronoarabinoxylan from sugarcane bagasse and straw2017In: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344, Vol. 156, p. 223-234Article in journal (Refereed)
    Abstract [en]

    Sugarcane bagasse and straw are generated in large volumes as by-products of agro-industrial production. They are an emerging valuable resource for the generation of hemicellulose-based materials and products, since they contain significant quantities of xylans (often twice as much as in hardwoods). Heteroxylans (yields of ca 20% based on xylose content in sugarcane bagasse and straw) were successfully isolated and purified using mild delignification followed by dimethyl sulfoxide (DMSO) extraction. Delignification with peracetic acid (PAA) was more efficient than traditional sodium chlorite (NaClO2) delignification for xylan extraction from both biomasses, resulting in higher extraction yields and purity. We have shown that the heteroxylans isolated from sugarcane bagasse and straw are acetylated glucuronoarabinoxylans (GAX), with distinct molecular structures. Bagasse GAX had a slightly lower glycosyl substitution molar ratio of Araf to Xylp to (0.5:10) and (4-O-Me)GlpA to Xylp (0.1:10) than GAX from straw (0.8:10 and 0.1:10 respectively), but a higher degree of acetylation (0.33 and 0.10, respectively). A higher frequency of acetyl groups substitution at position α-(1 → 3) (Xyl-3Ac) than at position α-(1 → 2) (Xyl-2Ac) was confirmed for both bagasse and straw GAX, with a minor ratio of diacetylation (Xyl-2,3Ac). The size and molecular weight distributions for the acetylated GAX extracted from the sugarcane bagasse and straw were analyzed using multiple-detection size-exclusion chromatography (SEC-DRI-MALLS). Light scattering data provided absolute molar mass values for acetylated GAX with higher average values than did standard calibration. Moreover, the data highlighted differences in the molar mass distributions between the two isolation methods for both types of sugarcane GAX, which can be correlated with the different Araf and acetyl substitution patterns. We have developed an empirical model for the molecular structure of acetylated GAX extracted from sugarcane bagasse and straw with PAA/DMSO through the integration of results obtained from glycosidic linkage analysis, 1H NMR spectroscopy and acetyl quantification. This knowledge of the structure of xylans in sugarcane bagasse and straw will provide a better understanding of the isolation-structure-properties relationship of these biopolymers and, ultimately, create new possibilities for the use of sugarcane xylan in high-value applications, such as biochemicals and bio-based materials.

  • 49.
    Moraisde Carvalho, Danila
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology. Univ Fed Vicosa, Dept Forestry Engn, Pulp & Paper Lab, BR-36570900 Vicosa, MG, Brazil.
    Martinez Abad, Antonio
    KTH, School of Biotechnology (BIO), Glycoscience.
    Colodette, Jorge Luiz
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology.
    Lindström, Mikael
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology.
    Vilaplana, Fransisco
    KTH, School of Biotechnology (BIO), Glycoscience. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Sevastyanova, Olena
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Comparative characterization of acetylated heteroxylan from eucalyptus, sugarcane bagasse and sugarcane strawManuscript (preprint) (Other academic)
  • 50.
    Moraisde Carvalho, Danila
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology. Univ Fed Vicosa, Dept Forestry Engn, Pulp & Paper Lab, BR-36570900 Vicosa, MG, Brazil.
    Sevastyanova, Olena
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Penna, Lais Souza
    da Silva, Brunela Pereira
    Lindstrom, Mikael E.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology.
    Colodette, Jorge Luiz
    Assessment of chemical transformations in eucalyptus, sugarcane bagasse and straw during hydrothermal, dilute acid, and alkaline pretreatments2015In: Industrial crops and products (Print), ISSN 0926-6690, E-ISSN 1872-633X, Vol. 73, p. 118-126Article in journal (Refereed)
    Abstract [en]

    The impact of hydrothermal, dilute acid, and alkaline pretreatments on the chemical structure of eucalyptus, sugarcane bagasse, and straw were compared with a view to their subsequent bioconversion into ethanol. Sugarcane bagasse and straw contain high amounts of extractives (15.0% and 12.2%, respectively), ash (2.3% and 7.9%, respectively), and silica (1.4% and 5.8%, respectively). If not properly corrected, the presence of silica would lead to the overestimation of the lignin, while high amounts of extractives would cause the overestimation of the content of sugars in biomass. Applying a novel approach through the use of complete mass balance, bagasse and straw were proven to contain lower amounts of lignin (18.0% and 13.9%, respectively) than previously reported for these raw materials, and certainly a much lower amount of lignin than eucalyptus (27.4%). The syringyl to guaiacyl units ratio (SIG) for lignin in bagasse and straw (1.1 and 0.5, respectively) was lower than that for eucalyptus (2.7), indicating a different reactivity during chemical pretreatments. The xylan content in sugarcane bagasse and straw was much higher than that in eucalyptus, with a significantly lower degree of substitution for uronic acids and acetyl groups. The sugarcane straw showed the highest mass loss during the investigated pretreatments, especially under alkaline conditions, with a total biomass yield of only 37.3%. During the hydrothermal and dilute acid treatments, mostly hemicelluloses were removed, followed by the formation a significant amount of pseudo-lignin structures, while the alkaline pretreatment affected the lignin content. With eucalyptus, the formation of structures similar in their behavior to extractives (i.e., soluble in toluene and ethanol, subsequently referred to as "pseudo-extractives") was observed during all three pretreatments, with 12.4% for hydrothermal, 18.9% for dilute acid, and 8.7% for alkaline pretreatment. This information, combined with actual yields, should be taken into account when assessing the impact of pretreatments on the chemical composition and structure of biomass.

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