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Publikasjoner (10 av 11) Visa alla publikasjoner
Svärd, A., Moriana, R., Brannvall, E. & Edlund, U. (2019). Rapeseed Straw Biorefinery Process. ACS Sustainable Chemistry and Engineering, 7(1), 790-801
Åpne denne publikasjonen i ny fane eller vindu >>Rapeseed Straw Biorefinery Process
2019 (engelsk)Inngår i: ACS Sustainable Chemistry and Engineering, ISSN 2168-0485, Vol. 7, nr 1, s. 790-801Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

A rapeseed straw biorefinery process was demonstrated with more than 50% of the straw recovered as products. Xylan with a weight-average molecular weight of 56 760 g/mol was extracted in an alkaline step. The straw residue was subjected to soda pulping, resulting in cellulose-rich fibers and a lignin-rich liquid fraction. The lignin contained syringyl and guaiacyl aromatic structural units in a 1/0.75 ratio. The cellulose pulp was bleached, resulting in a cellulose fraction of 85% purity and a crystallinity index (CI) of 83%. Two grades of nanocellulose, CNF and CNC, were isolated from the bleached pulp. The CNF was very heterogeneous in size with an average diameter of 4 nm and an average length of 1177 nm. The CNC had an average diameter of 6 nm and an average particle length of 193 nm. CNF and CNC had good thermal stability and an aspect ratio of 294 and 32, respectively.

sted, utgiver, år, opplag, sider
American Chemical Society (ACS), 2019
Emneord
Canola straw, Biorefinery, Xylan, Lignin, Nanocellulose, Hydrothermal extraction
HSV kategori
Identifikatorer
urn:nbn:se:kth:diva-242988 (URN)10.1021/acssuschemeng.8b04420 (DOI)000455288800083 ()2-s2.0-85058836615 (Scopus ID)
Forskningsfinansiär
Swedish Research Council Formas, 2013-844
Merknad

QC 20190205

Tilgjengelig fra: 2019-02-05 Laget: 2019-02-05 Sist oppdatert: 2019-10-08bibliografisk kontrollert
Svärd, A., Sterner, M. & Edlund, U. (2018). Bioplastics and composites from plant heteropolysaccharides. Paper presented at 255th National Meeting and Exposition of the American-Chemical-Society (ACS) - Nexus of Food, Energy, and Water, MAR 18-22, 2018, New Orleans, LA. Abstract of Papers of the American Chemical Society, 255
Åpne denne publikasjonen i ny fane eller vindu >>Bioplastics and composites from plant heteropolysaccharides
2018 (engelsk)Inngår i: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 255Artikkel i tidsskrift, Meeting abstract (Annet vitenskapelig) Published
sted, utgiver, år, opplag, sider
American Chemical Society (ACS), 2018
HSV kategori
Identifikatorer
urn:nbn:se:kth:diva-240170 (URN)000435537702808 ()
Konferanse
255th National Meeting and Exposition of the American-Chemical-Society (ACS) - Nexus of Food, Energy, and Water, MAR 18-22, 2018, New Orleans, LA
Merknad

QC 20190111

Tilgjengelig fra: 2019-01-11 Laget: 2019-01-11 Sist oppdatert: 2019-01-11bibliografisk kontrollert
Edlund, U., Svärd, A., Sterner, M. & Wahlström, N. (2018). Engineered polysaccharide materials from biorefining of terrestrial and marine biomass. Paper presented at 256th National Meeting and Exposition of the American-Chemical-Society (ACS) - Nanoscience, Nanotechnology and Beyond, AUG 19-23, 2018, Boston, MA. Abstract of Papers of the American Chemical Society, 256
Åpne denne publikasjonen i ny fane eller vindu >>Engineered polysaccharide materials from biorefining of terrestrial and marine biomass
2018 (engelsk)Inngår i: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 256Artikkel i tidsskrift, Meeting abstract (Annet vitenskapelig) Published
sted, utgiver, år, opplag, sider
AMER CHEMICAL SOC, 2018
HSV kategori
Identifikatorer
urn:nbn:se:kth:diva-238559 (URN)000447600002536 ()
Konferanse
256th National Meeting and Exposition of the American-Chemical-Society (ACS) - Nanoscience, Nanotechnology and Beyond, AUG 19-23, 2018, Boston, MA
Merknad

QC 20181105

Tilgjengelig fra: 2018-11-05 Laget: 2018-11-05 Sist oppdatert: 2018-12-17bibliografisk kontrollert
Svärd, A., Brännvall, E. & Edlund, U. (2018). Modified and thermoplastic rapeseed straw xylan: A renewable additive in PCL biocomposites. Industrial crops and products (Print), 119, 73-82
Åpne denne publikasjonen i ny fane eller vindu >>Modified and thermoplastic rapeseed straw xylan: A renewable additive in PCL biocomposites
2018 (engelsk)Inngår i: Industrial crops and products (Print), ISSN 0926-6690, E-ISSN 1872-633X, Vol. 119, s. 73-82Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Xylan extracted from rapeseed straw was chemically modified to gain hydrophobic and thermoplastic properties via macroinitiator formation followed by a free radical grafting-from polymerization with octadecyl acrylate. Biocomposites were then prepared by incorporation of 5 or 20% (w/w) rapeseed straw xylan into a poly(epsilon-caprolactone) (PCL) matrix by melt extrusion. The grafted xylan was homogeneously distributed within the biocomposite and reinforced the PCL matrix while at the same time preserving the ability to elongate to tensile strains > 500%. Analogous biocomposites made from unmodified xylan in a PCL matrix resulted in heterogeneous mixtures and brittle tensile properties.

sted, utgiver, år, opplag, sider
Elsevier, 2018
Emneord
Biocomposite, Grafting, Hemicellulose, Rapeseed/canola straw, Thermoplastic, Xylan
HSV kategori
Identifikatorer
urn:nbn:se:kth:diva-227505 (URN)10.1016/j.indcrop.2018.03.067 (DOI)000432763800009 ()2-s2.0-85045072624 (Scopus ID)
Forskningsfinansiär
Swedish Research Council Formas, 2013-844
Merknad

QC 20180518

Tilgjengelig fra: 2018-05-18 Laget: 2018-05-18 Sist oppdatert: 2018-09-07bibliografisk kontrollert
Svärd, A., Brännvall, E. & Edlund, U. (2017). Corrigendum to “Rapeseed straw as a renewable source of hemicelluloses: Extraction, characterization and film formation” [Carbohydrate Polymers 133 (2015) 179–186](S0144861715006529)(10.1016/j.carbpol.2015.07.023). Carbohydrate Polymers, 174, 1240
Åpne denne publikasjonen i ny fane eller vindu >>Corrigendum to “Rapeseed straw as a renewable source of hemicelluloses: Extraction, characterization and film formation” [Carbohydrate Polymers 133 (2015) 179–186](S0144861715006529)(10.1016/j.carbpol.2015.07.023)
2017 (engelsk)Inngår i: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344, Vol. 174, s. 1240-Artikkel i tidsskrift (Annet vitenskapelig) Published
Abstract [en]

The authors regret that the original version of this article unfortunately contained a mistake in Table 5. The correct Table 5 and associated text is given below. “The rapeseed hemicellulose films presented here had strain-at-break values of 70% (C) and 90% (H), even with no added plasticizers (Table 5).” The authors would like to apologise for any inconvenience caused.

sted, utgiver, år, opplag, sider
Elsevier, 2017
HSV kategori
Identifikatorer
urn:nbn:se:kth:diva-234655 (URN)10.1016/j.carbpol.2017.07.037 (DOI)2-s2.0-85026534602 (Scopus ID)
Tilgjengelig fra: 2018-09-07 Laget: 2018-09-07 Sist oppdatert: 2018-12-14bibliografisk kontrollert
Svärd, A., Brännvall, E. & Edlund, U. (2017). Rapeseed straw polymeric hemicelluloses obtained by extraction methods based on severity factor. INDUSTRIAL CROPS AND PRODUCTS, 95, 305-315
Åpne denne publikasjonen i ny fane eller vindu >>Rapeseed straw polymeric hemicelluloses obtained by extraction methods based on severity factor
2017 (engelsk)Inngår i: INDUSTRIAL CROPS AND PRODUCTS, ISSN 0926-6690, Vol. 95, s. 305-315Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Rapeseed straw consists of a hard epidermis that is rich in hemicellulose and lignin and a sponge-like interior that consists mainly of cellulose. The stems were subjected to water, alkali or acid as extraction medium. The effects of the extraction conditions were quantified using severity factors and by comparing the effects of different extraction pHs, temperatures and times. Extraction with alkali resulted in a higher yield, 47 g/100 g straw in, compared to water, 6 g/100 g straw in, or an acidic, 5 g/100 g straw in, extraction process. An increase in temperature improved the extraction yield; in particular, more xylan was extracted at an elevated temperature and higher alkalinity. However, at high alkalinity, increased extraction temperatures led to a reduction in the recovery of glucomannan. The highest molecular weights (similar to 35,000 g/mol) of the extracted hemicelluloses were obtained using extraction procedures with 1.5 M NaOH at 110 degrees C and autohydrolysis at 150 degrees C. While these two parameter settings had very similar severity factors, extraction under basic conditions afforded an extract rich in xylan and low in lignin content, whereas autohydrolysis generated a glucomannan-rich extract.

sted, utgiver, år, opplag, sider
Elsevier, 2017
Emneord
Rapeseed/canola straw, Extraction, Autohydrolysis, Severity factor, Hemicellulose
HSV kategori
Identifikatorer
urn:nbn:se:kth:diva-200198 (URN)10.1016/j.indcrop.2016.10.038 (DOI)000390621600035 ()2-s2.0-85004143297 (Scopus ID)
Merknad

QC 20170202

Tilgjengelig fra: 2017-02-02 Laget: 2017-01-23 Sist oppdatert: 2018-09-07bibliografisk kontrollert
Svärd, A., Sevastyanova, O., Dobele, G., Jurkjane, V. & Brännvall, E. (2016). COST Action FP1105: effect of raw materials and pulping conditions on the characteristics of dissolved kraft lignins. Holzforschung, 70(12), 1105-1114
Åpne denne publikasjonen i ny fane eller vindu >>COST Action FP1105: effect of raw materials and pulping conditions on the characteristics of dissolved kraft lignins
Vise andre…
2016 (engelsk)Inngår i: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 70, nr 12, s. 1105-1114Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

The composition, molecular weight (MW), and chemical structure of technical lignins as byproducts of pulping influence their application in terms of physical and chemical properties, reactivity, and performance. It is important to know how the analytical data of technical lignins are influenced by the wood species and the parameters of pulping. The present study focuses on kraft pulping and how the wood species (eucalyptus, pine, and spruce) and variable cooking times influence the characteristics of dissolved lignins. The black liquor (BL) was recovered after three different cooking times and the precipitated lignin was characterized by total acid hydrolysis including the determination of the acid insoluble part (Klason lignin, KL) and the sugars in the hydrolysate, elemental analysis, 31P NMR spectroscopy, analytical pyrolysis (Py-GC/MS), gel permeation chromatography (GPC), thermogravimetry (TG), and differential scanning calorimetry (DSC). The results indicate that the phenolic OH content, MW and glass transition temperature increased with longer cooking times for the softwood (SW) lignins. These lignins had also a higher MW (M-w 5500-8000 g mol(-1)), than the eucalyptus lignin (M-w 2200-2400 g mol(-1)). Eucalyptus lignin had higher sulfur content compared to SW.

sted, utgiver, år, opplag, sider
Walter de Gruyter, 2016
Emneord
DSC, eucalyptus, GPC, kraft cooking, lignin, lignin precipitation, pine, P-31-NMR, Py-GC/MS, spruce, TGA
HSV kategori
Identifikatorer
urn:nbn:se:kth:diva-199495 (URN)10.1515/hf-2016-0057 (DOI)000389466800002 ()2-s2.0-84998554796 (Scopus ID)
Merknad

QC 20170118

Tilgjengelig fra: 2017-01-18 Laget: 2017-01-09 Sist oppdatert: 2017-11-29bibliografisk kontrollert
Svärd, A. (2016). Extraction of polymeric rapeseed straw hemicelluloses for renewable films. (Licentiate dissertation). Stockholm: Kungliga Tekniska högskolan
Åpne denne publikasjonen i ny fane eller vindu >>Extraction of polymeric rapeseed straw hemicelluloses for renewable films
2016 (engelsk)Licentiatavhandling, med artikler (Annet vitenskapelig)
Abstract [en]

Polymeric hemicelluloses with high molecular weight were extracted from rapeseed straw with a straight forward hydrothermal extraction method, evaluated and refined by statistical factorial screening design and ‘severity factor’ analysis. The influence of the extraction conditions, time, temperature and pH of the extraction liquid, on the composition, molecular weight, yield and properties was unveiled. The initial statistical screening design provided critical knowledge in how the extraction parameters affect yield, lignin and sugar composition as well as molecular weight of the extracts. A more elaborate extraction study which encompassed a greater temperature range and variation of the pH in the hydrothermal liquid combined with ‘severity factor’ modeling on the molecular weight of the extracts provided deeper insights of the effect of the extraction conditions. Water and acid extraction resulted in glucomannan rich extracts. Glucomannan isolated with acid was more degraded than the glucomannan isolated with water. From an environmentally perspective water extraction is preferred to obtain glucomannan due to the corrosive nature of acid. The molecular weight of the dissolved glucomannan during water extraction increased with temperature. Xylan was co-extracted at the higher extraction temperature. Alkaline extraction yielded an extract rich in xylan, where the total amount and the molecular weight of xylan increased with alkali charge. The xylan was more degraded at the highest temperature, 140 °C, and the highest alkali charge. All different extractions yielded co-extracted lignin, especially during high charge of alkali, but the straw was never fully delignified or the cellulose fibres liberated. Some extracts, selected from the statistical screening study, were utilized as raw materials for renewable plastic films.  The glucomannan films were very fragile, while the xylan films had remarkable strain-at-break of 60 – 80 % without any added plasticizer.

sted, utgiver, år, opplag, sider
Stockholm: Kungliga Tekniska högskolan, 2016. s. 55
Serie
TRITA-CHE-Report, ISSN 1654-1081 ; 2016:16
Emneord
rapeseed straw/canola straw, hemicellulose, xylan, mannan, extraction, characterization, severity factor, hemicellulose film
HSV kategori
Forskningsprogram
Kemi
Identifikatorer
urn:nbn:se:kth:diva-185737 (URN)978-91-7595-939-9 (ISBN)
Presentation
2016-05-20, K2, Teknikringen 28, Stockholm, 10:00 (engelsk)
Opponent
Veileder
Forskningsfinansiär
Swedish Research Council Formas, 2013-844
Merknad

QC 20160428

Tilgjengelig fra: 2016-04-28 Laget: 2016-04-26 Sist oppdatert: 2016-04-28bibliografisk kontrollert
Svärd, A., Brännvall, E. & Edlund, U. (2016). Rapeseed straw extraction yields hemicelluloses for renewable materials. Abstract of Papers of the American Chemical Society, 251
Åpne denne publikasjonen i ny fane eller vindu >>Rapeseed straw extraction yields hemicelluloses for renewable materials
2016 (engelsk)Inngår i: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 251Artikkel i tidsskrift, Meeting abstract (Annet vitenskapelig) Published
sted, utgiver, år, opplag, sider
AMER CHEMICAL SOC, 2016
HSV kategori
Identifikatorer
urn:nbn:se:kth:diva-242702 (URN)000431903802557 ()
Merknad

QC 20190220

Tilgjengelig fra: 2019-02-20 Laget: 2019-02-20 Sist oppdatert: 2019-02-20bibliografisk kontrollert
Svärd, A., Brännvall, E. & Edlund, U. (2015). Rapeseed straw as a renewable source of hemicelluloses: Extraction, characterization and film formation. Carbohydrate Polymers, 133, 179-186
Åpne denne publikasjonen i ny fane eller vindu >>Rapeseed straw as a renewable source of hemicelluloses: Extraction, characterization and film formation
2015 (engelsk)Inngår i: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344, Vol. 133, s. 179-186Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

Polymeric hemicelluloses were extracted by autohydrolysis and alkali from a biomass feed consisting of the stems of rapeseed straw according to a full statistical factorial screening design. Water extraction yielded fractions rich in galactoglucomannan, while alkaline extraction yielded primarily xylan. The extracted galactoglucomannan and xylans had similar molecular weights, while the yield of xylan was higher than the yield of galactoglucomannan. The extracted hemicellulose fractions also contained some lignin (7-15%) and traces of Ca, K, Na, and Si. Free-standing films were prepared from the hemicellulose fractions with different xylan:galactoglucomannan ratios. The rapeseed xylan films showed strain-to-break values >60% without any added plasticizers.

Emneord
Rapeseed/canola straw, Extraction, Autohydrolysis, Alkaline extraction, Xylan, Glucomannan, Film
HSV kategori
Identifikatorer
urn:nbn:se:kth:diva-175899 (URN)10.1016/j.carbpol.2015.07.023 (DOI)000361920900024 ()26344270 (PubMedID)2-s2.0-84937926293 (Scopus ID)
Forskningsfinansiär
Swedish Research Council Formas, 2013-844
Merknad

QC 20151113

Tilgjengelig fra: 2015-11-13 Laget: 2015-10-26 Sist oppdatert: 2018-09-07bibliografisk kontrollert
Organisasjoner
Identifikatorer
ORCID-id: ORCID iD iconorcid.org/0000-0002-2041-5786