Aqueous zinc-ion batteries have gained significant interest, offering several distinct advantages over conventional lithium-ion batteries owing to their compelling low cost, enhanced battery safety, and excellent environmental friendliness. Nevertheless, the unfortunate growth of zinc dendrites during cycling leads to poor electrochemical performance of zinc batteries, primarily attributed to the diminished wet mechanical properties and limited electrolyte uptake of existing commercial separators. Herein, a bio-based separator was developed from sustainable resources using natural polymers derived from wood pulp to replace fossil-based polyolefin separators. The inherent hydrophilicity and swelling ability of cellulose fibers provide separators with superior electrolyte wettability and uptake. Notably, the structural reinforcement provided by lignin, especially after hot pressing, enhances the separator's wet mechanical integrity and performance during battery cycling. These improvements contribute to the separator's more stable electrochemical performance and improved ion transport properties. Separators composed of lignin-rich microfibrillated cellulose fibers showed superior dimensional stability under heat compared to Celgard, ensuring higher thermal safety and enhanced performance of aqueous zinc-ion batteries. Our results reveal the great potential of lignin-rich cellulose-based separators for future zincion batteries.

Brownstock washing, a critical process in cleansing kraft pulp, removes dissolved lignin residues from the pulp after it has passed through the cooking digester. It plays a significant role in kraft pulp mills by enhancing economic efficiency and environmental sustainability. Improved washing efficiency leads to better pulp quality and more effective recovery of cooking chemicals. Our study aimed to better understand the impact of different chemical compositions in washing liquors on washing performance. We tested a range of washing liquors, including neutral solutions (deionized water, 1M NaCl, 3M NaCl, 1M Na2SO4) and alkaline solutions (tap water, washing liquor composed of 0.35M NaOH and 1M Na2SO4, and white liquor with 50 g[OH]/l and 8.77 g[HS]/l). These liquors were evaluated for their efficacy in maximizing lignin extraction. Our findings suggest that salt solutions generally reduce washing efficiency. Deionized water and white liquor proved to be the most efficient washing agents, while high-concentration salts and those with high ionic strength negatively impacted washing efficiency. This suggests that brownstock washing may not be operating at its full potential.

This study investigates lignin nanoparticles (LNPs) from spruce and Eucalyptus kraft lignins as sustainable additives for sunscreen formulations. The lignins and their nanoparticles were characterized using spectroscopic, chromatographic, and microscopic techniques and incorporated into oil-in-water sunscreen emulsions, where they were evaluated for UV-blocking efficiency, stability, and rheological properties. Results demonstrated that LNPs significantly enhanced UV protection, with spruce kraft lignin nanoparticles providing superior broad-spectrum coverage (280–400 nm) and an SPF of 12.94, compared to Eucalyptus lignin nanoparticles, which primarily absorbed in the UVB range (280–320 nm) and reached an SPF of 7.00. Additionally, LNPs improved emulsion stability through Pickering stabilization and enhanced rheological properties, making them promising eco-friendly and multifunctional sunscreen additives.

The study presents cellulose-based membranes derived from lignin-rich (unbleached high-kappa number softwood and hardwood) and lignin-free (fully bleached softwood) kraft pulps for the removal of cationic dyes from both simulated and real aqueous environmental systems. Characterization techniques revealed that the lignin-enriched cellulose-based membranes exhibited enhanced wet mechanical properties and a broader range of functional groups. The functional diversity inherent in lignin-containing membranes resulted in superior adsorption capacity for dyes such as Methylene Blue and Crystal Violet, compared to lignin-free counterparts. Detailed adsorption performance metrics—including kinetics, equilibrium studies, and the effects of pH and ionic strength—were thoroughly investigated. The adsorption capacity was 99–102 μmol g−1 for hardwood-derived membranes and 79–85 μmol g−1 for softwood-derived membranes at 25 °C. The process followed the pseudo-first-order kinetic model, likely due to the membranes' low porosity and energy homogeneity, which facilitated rapid adsorption. Electrostatic interactions played a pivotal role in dye attraction, while pH and ionic strength studies emphasized the importance of hydrogen bonding between cationic dyes and lignocellulose-based membranes. This research highlights the significance of utilizing cellulose-based membranes with enhanced lignin content in water purification, demonstrating their effective adsorption capabilities in both controlled and real-world environments. The approbation tests of these membranes showcased their substantial potential for practical water purification applications, contributing to the development of sustainable and efficient water treatment solutions.

This work has focused on oxygen's role in the delignification process within the context of pulp production. We have investigated the role of oxygen in a complex set of chemical reactions taking place during this process, including both oxidative and non-oxidative reactions. This study explores the impact of pH changes during the oxygen delignification process and the characteristics of the resulting pulps. Additionally, this research examines the effect of oxygen, by comparing conventional oxygen delignification with trials using air and nitrogen. Industrial softwood kraft pulps with a kappa number of 35 were subjected to delignification for 20-120 min under alkaline conditions. The resulting pulps were assessed for kappa number, intrinsic viscosity, fiber charge, and ISO brightness. An important observation from this research is the reduction in lignin molecular weight upon exposure to oxygen and air, suggesting depolymerization reactions facilitated by oxygen species, whereas nitrogen exposure results in less pronounced changes. This finding underscores the impact of oxygen in altering lignin structure, thus informing the selectivity and effectiveness of the delignification process.

Polymer binder selection greatly impacts electrode performance, production, and recyclability in batteries and energy storage systems. We introduce a novel family of polymer binders that provide several key advantages over traditional binders in Li-ion batteries. Our findings show that in-situ cross-linked networks of eco-friendly polyesters bearing pendant carboxylic moieties can serve as superior binders for electrodes. When tested specifically in high‑silicon-content anodes, the electrodes exhibit high initial coulombic efficiency and sustain impressive specific capacity retention after 300 cycles. They reach approximately 2500 mAh/g, compared to 1580 mAh/g for electrodes using conventional PAA binders. Furthermore, the anode shows stable cycling performance when paired with NMC532 cathodes in full Li-ion cell tests. Notably, the transition of silicon from intermediate phases to its fully lithiated state is more efficient with the polyester binder, attributed to the formation of a more stable solid-electrolyte interphase (SEI) layer and reduced impedance. We assign the high performance of our binder to the presence of the polar groups, e.g. carbonyl, in the primary polymer chain, along with the end functional moieties, promoting Li+ solvation and transport, resulting in a high ionic conductivity of the binder. Moreover, the inherent flexibility in the formulations of the polyesters enables fine-tuning of properties such as adhesion, elasticity, and a suitable glass transition temperature, all of which could be customized to optimize battery performance. Produced from renewable feedstocks and adopting water-based or solvent-free fabrication processes, these polyesters offer a fully sustainable solution from production to recycling at the end of the battery's life.

The expanding field of lignin-containing nanocellulose offers a sustainable alternative to fossil-based substances in applications such as packaging, coatings, and composites. This has underscored the importance to explore the impact of raw materials due to the complexities of lignin structures and different raw fiber characteristics, which plays a significant role in determining the properties of the resultant lignin-rich cellulose materials. This study presents a detailed investigation and comparison on the production and structure-property relationships of lignin-containing microfibrillated cellulose (LMFC) fibers prepared from unbleached softwood and hardwood kraft pulps. The microfibrillation process was analyzed for both softwood and hardwood pulps, comparing the results across various stages of fibrillation. Distinguishing features of lignin structures in softwood and hardwood pulps were identified through Py-GC/MS analysis. Additionally, Digital Image Correlation was employed to investigate the varying failure patterns in LMFC films derived from different wood species. Softwood-derived LMFC films demonstrate less strain-concentrated regions and strain variation, attributed to the formation of more physical crosslinking joints by the elongated fibers. Consequently, softwood-origin LMFC films displayed superior load-sharing and enhanced tensile strength (287 MPa) compared to those derived from hardwood. Additionally, the denser lignin structures in unbleached softwood pulp further boosted the stiffness of resultant softwood-derived films. Upon recycling, LMFC films exhibited superior recovery of mechanical properties following drying, suggesting their significant potential for widespread commercial use.

The primary objective of this investigation is to evaluate how the incorporation of lignin and high-viscosity modifiers impacts the performance of asphalt binders. Lignin-modified asphalt binder (LBA) and lignin-high viscosity modifier composite-modified asphalt binder (LHA) were created by blending 5 % and 15 % lignin, respectively. To understand the physicochemical interactions, Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) were employed to analyze functional groups, thermal properties, and phase changes. Additionally, the linear rheological behavior and nonlinear rheological behavior were evaluated through frequency sweep and multiple stress creep recovery tests. The findings suggest that lignin blends physically with the asphalt binder and high-viscosity modifier without a chemical reaction. Although the onset pyrolysis temperature of lignin is significantly lower than that of asphalt binders, due to its relatively low content, the thermal decomposition of lignin-modified asphalt binders is primarily controlled by the asphalt binder itself and still exceeds the construction temperature. However, lignin incorporation increases the asphalt binder's glass transition temperature, potentially affecting low-temperature performance. Lignin significantly enhances the modulus in the high-frequency region of both unmodified and high-viscosity modified asphalt binder. However, it has a negative effect on the modulus in the low-frequency region of high-viscosity modified asphalt binder. Furthermore, nonlinear creep recovery test results demonstrate that lignin positively contributes to the deformation resistance of unmodified asphalt binder in a content-dependent manner, whereas it reduces the elastic behavior and deformation resistance of high-viscosity modified asphalt binder. In addition, low levels of lignin increase the stress sensitivity of binders, while high levels of lignin decrease it. Despite these effects, the performance of lignin and high-viscosity additive composite-modified asphalt binder remains superior to that of unmodified asphalt binder. These findings offer valuable insights into the combined use of lignin and polymers in asphalt binder modification.

Effective removal of organic and inorganic impurities by adsorption technique requires the preparation of new materials characterized by low production costs, significant sorption capacity, and reduced toxicity, derived from natural and renewable sources. To address these challenges, new adsorbents have been developed in the form of polymer microspheres based on ethylene glycol dimethacrylate (EGDMA) and vinyl acetate (VA) (EGDMA/VA) containing starch (St) modified with boric acid (B) and dodecyl-S-thiuronium dodecylthioacetate (DiTDTA) for the removal of dyes: C.I. Basic Blue 3 (BB3) and C.I. Acid Green 16 (AG16) and heavy metal ions (M(II)): Cu(II), Ni(II), and Zn(II) from water and wastewater. The adsorbents were characterized by ATR/FT-IR, DSC, SEM, BET, EDS, and pHPZC methods. These analyses demonstrated the successful modification of microspheres and the increased thermal resistance resulting from the addition of the modified starch. The point of zero charge for EGDMA/VA was 7.75, and this value decreased with the addition of modified starch (pHPZC = 6.62 for EGDMA/VA-St/B and pHPZC = 5.42 for EGDMA/VA-St/DiTDTA). The largest specific surface areas (SBET) were observed for the EGDMA/VA microspheres (207 m2/g), and SBET value slightly decreases with the modified starch addition (184 and 169 m2/g) as a consquence of the pores stopping by the big starch molecules. The total pore volumes (Vtot) were found to be in the range from 0.227 to 0.233 cm3/g. These materials can be classified as mesoporous, with an average pore diameter (W) of approximately 55 Å (5.35–6.10 nm). The SEM and EDS analyses indicated that the EGDMA/VA microspheres are globular in shape with well-defined edges and contain 73.06% of carbon and 26.94% of oxygen. The microspheres containing modified starch exhibited a loss of smoothness with more irregular shape. The adsorption efficiency of dyes and heavy metal ions depends on the phases contact time, initial adsorbate concentration and the presence of competing electrolytes and surfactants. The equilibrium data were better fitted by the Freundlich isotherm model than by the Langmuir, Temkin, and Dubinin-Radushkevich models. The highest experimental adsorption capacities were observed for the BB3 dye which were equal to 193 mg/g, 190 mg/g, and 194 mg/g for EGDMA/VA, EGDMA/VA-St/B, EGDMA/VA-St/DiTDTA, respectively. The dyes and heavy metal ions were removed very rapidly and the time required to reach system equilibrium was below 20 min for M(II), 40 min for BB3, and 120 min for AG16. 50% v/v methanol and its mixture with 1 M HCl and NaCl for dyes and 1 M HCl for M(II) desorbed these impurities efficiently.

Samples of Eucalyptus dunnii with high calcium content have less good pulping properties regarding delignification and polysaccharide degradation, as it was shown by us earlier. In this work, we tested the addition of black liquor and green liquor to the Eucalyptus dunnii chips before kraft pulping, Specific improvements were obtained with both liquors, but the most substantial effect was observed with the green liquor, where even wood with the highest calcium content was pulped with a good result. Delignification was faster, and viscosity losses (degree of polymerization of cellulose) were higher for samples treated with green liquor prior to kraft pulping. Bleaching experiments showed that the bleachability of the green liquor-treated pulp was virtually the same as for a control pulp and that the higher viscosity of the bleached pulp was maintained. Possible chemical explanations for the results obtained are discussed.