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An innovative binary biol-based deep eutectic solvent (DES), specifically ethylamine hydrochloride-ethylene glycol (EaCl-EG), was developed for efficient pretreatment of eucalyptus biomass. This DES exhibited superior performance in achieving high delignification (85.0%) and xylan removal (80.0%), while preserving a significant amount of cellulose (94.5%) compared to choline chloride-based DES. Notably, the pretreated eucalyptus residues showed a remarkable glucose yield of over 92.5%, representing a substantial enhancement of up to 15 times compared to untreated eucalyptus. Furthermore, the pretreated liquor yielded high-purity lignin with a yield of 97.8%, characterized by well-preserved β-O-4 structure and nanoscale dimensions. These lignin nanoparticles (LNPs) were subsequently self-assembled into lignin nanobottles (LNBs), adding further value to the pretreatment process. The proposed novel binary EaCl-EG DES presented great potential as an efficient pretreatment solvent for future biomass fractionation processes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Camellia oleifera shell (COS) is a renewable biomass resource abundant in lignin with significant potential for producing phenolic monomers. However, the dearth of research has led to considerable resource wastage and environmental pollution. Herein, reductive catalytic fractionation (RCF) of COS was performed using noble metal catalysts in different solvents. An 11.1 wt% yield of phenolic monomers was achieved with 91% selectivity toward propylene-substituted monomers in H 2 O/EtOH (3:7, v/v) cosolvent under N 2 atmosphere. Notably, the highest phenolic monomer yield of 17.0 wt% was obtained with impressive selectivity (86.9%) toward propanol-substituted monomers in the presence of H 2 . The GPC analysis and 2D HSQC NMR spectra indicated the effective depolymerization of lignin oligomers with catalysts. Phenolic monomers with ethyl, propyl, or propanol side chain could be produced from lignin-derived oligomers through hydrogenolysis, hydrogenation, and decarboxylation reactions. Overall, this study has paved the way for the valorization of COS lignin through the RCF strategy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The utilization of biomass pyrolysis is a crucial approach for sustainable development. This study used the typical biomass of pine (PI), rice husk (RH), and corn straw (ST) as feedstocks to evaluate the pyrolysis mechanisms, features and conversion mechanisms of the phenol tar product. The phenolic gaseous products were more trailing in ST, which mostly concentrated around 320-500 °C. Primary phenol tar is produced from lignin through the homolytic cleavage of β-O and α-O, and C-C bond breakage, primarily occurring before 550 °C. As the degree of aromatization increases, the oxygenates progressively deoxygenate, and the primary tar demethoxylates to form secondary tar as the temperature increases. The pyrolysis of cellulose produces H radicals, which aid the transformation of lignin into phenol tar. This study can provide a theoretical basis for biomass pyrolysis to select the appropriate process parameters to improve the quality of bio-oil and regulate phenol tar products., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Volatile-char interaction is an important phenomenon in biomass thermal conversion process, which significantly contributes to the decomposition, deoxygenation and upgrading of biomass. However, the deep insight into volatile-char interaction mechanisms between hemicellulose, cellulose and lignin is currently unclear. In this work, above mechanism was studied through systematic single-/bi-component torrefactions and the follow-up char analysis. Results demonstrate that only hemicellulose volatile and cellulose char interaction exists during torrefaction at 250 °C, causing over 19.9 wt% of mass loss and 27.3 wt% of O removal for cellulose. This volatile-char interaction causes significant depolymerization and amorphization of cellulose by hydrolysis, acid hydrolysis and esterification reactions. The depolymerized and amorphous cellulose partly thermally decomposes to dehydrated sugars and aromatic compounds through dehydroxylation and aromatization reactions. A volatile-char interaction mechanism model is thus developed. This work provides theoretical insight into biomass thermal conversion and provides basis for the development of new thermochemical method., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Carbon quantum dots (CQDs) were successfully synthesized from carbohydrate-rich residue of birch obtained following the lignin-first strategy. The optical and physicochemical properties of the CQDs were studied, along with their potential for photocatalytic pollutant degradation. By combining solvothermal and chemical oxidation methods, the product yield of CQDs from carbohydrate-rich residue reached 8.1 wt%. Doping nitrogen enhances the graphitization of CQDs and introduces abundant amino groups to the surface, thereby boosted the quantum yield significantly from 8.9 % to 18.7 %-19.3 %. Nitrogen-doped CQDs exhibited efficient photocatalytic degradation of methylene blue, reaching 37 % within 60 min, with a kinetic degradation rate of 0.00725 min -1 . This study demonstrates that carbohydrate-rich residue obtained from lignin-first strategy are ideal precursors for synthesizing CQD with high mass yield and quantum yield by combining solvothermal treatment and chemical oxidation methods, offering a novel approach for the utilization of whole biomass components following the lignin-first strategy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Lignin represents a promising source of renewable energy. The development of CLEO (Cold processed Lignin Ethanol Oil) fuel introduces a novel lignin valorization approach, proposing its potential as maritime biofuel. However, its industrial success depends on enhancing fractionation yields and reducing solvent evaporation, which necessitates a detailed analysis of lignin properties, solvent types, and process parameters. By using novel combinations of biobased solvents, yields improved from 34 wt% to 49-53 wt% by using 30 wt% water or 40 wt% glycerol in ethanol, where Hildebrand Solubility Parameters emerged as indicative tool for increasing yields. Experiments on solid-to-liquid (S:L) ratios revealed a good balance between yield and lignin dispersion concentration at an S:L of 1:2.5. Producing CLEO with an improved solvent composition and S:L ratio resulted in 89 wt% yield while eliminating solvent evaporation requirements. This study highlights the potential for enhancing CLEO production efficiency and advancing it to industrial scale., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Tor Ivan Simonsen reports financial support was provided by The Energy Technology Development and Demonstration Programme. Yohanna Orozco Cabrera has patent #11306264 issued to A.P. MØLLER—MÆRSK A/S, KØBENHAVNS UNIVERSITET., (Copyright © 2024. Published by Elsevier Ltd.)

In this study, magnetic biochar was synthesized by doping Fe 3 O 4 onto the biochar surface followed by analysis of its properties. The efficiency of methylene blue (MB) removal through the combined processes of adsorption and photolysis was assessed. The presence of Fe 3 O 4 on the biochar surface was confirmed using Raman spectroscopy and X-ray photoelectron spectroscopy. The magnetic biochar, after MB adsorption, showed a magnetism of 39.50 emu/g leading to a 97.07 % recovery rate. The specific surface area of biochar was higher (380.68 m 2 /g) than that of magnetic biochar (234.46 m 2 /g), and the maximum adsorption capacity of MB was higher in the biochar (0.03 mg/g) than that in magnetic biochar (0.02 mg/g) under the optimal conditions for MB adsorption. The MB adsorption experiments using biochar or magnetic biochar were optimally conducted under 10-20 mg/L MB concentration, 1 g biochar dosage, pH 12, 200 rpm rotation speed, 25 °C temperature, and 30 min duration. Under dark conditions, biochar had a higher MB removal rate, at 83.91 %, compared to magnetic biochar, at 78.30 %. Under visible light (λ > 425 nm), magnetic biochar effectively removed MB within 10 min, highlighting the synergistic effect of adsorption and photolysis. MB is physically and chemically adsorbed by the monolayer on the surface of EB and EMB according to adsorption behavior., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The synthetic superabsorbent polymers (SAPs) market is experiencing significant growth, with applications spanning agriculture, healthcare, and civil engineering, projected to increase from $9.0 billion USD in 2019 to $12.9 billion USD by 2024. Despite this positive trend, challenges such as fluctuating raw material costs and lower biodegradability of fossil fuel-based SAPs could impede further expansion. In contrast, cellulose and its derivatives present a sustainable alternative due to their renewable, biodegradable, and abundant characteristics. Lignocellulosic biomass (LCB), rich in cellulose and lignin, shows promise as a source for eco-friendly superabsorbent polymer (SAP) production. This review discusses the applications, challenges, and future prospects of SAPs derived from lignocellulosic resources, focusing on the cellulose extraction process through fractionation and various modification and crosslinking techniques. The review underscores the potential of cellulose-based SAPs to meet environmental and market needs, offering a viable path forward in the quest for more sustainable materials., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

A novel ternary deep eutectic solvent (TDES), consisting of zinc chloride, ethylene glycol and alpha hydroxy carboxylic acids (i.e., glycolic acid, citric acid and malic acid), was first proposed to effectively fractionate and convert willow (Salix matsudana cv. Zhuliu) into fermentable sugar. In particular, the zinc chloride/ethylene glycol/malic acid (ZnCl 2 /EG/MA) TDES system showed remarkable fractionation performance with 91.66 % xylan and 90.12 % lignin removals at 130 °C for 1.5 h, resulting in 96.01 % glucose yield in the subsequent enzymatic hydrolysis stage. Moreover, the regenerated lignin showed regular nanoparticle morphology and good antioxidant properties. Even after four recycling, the TDES showed 70.16 % of delignification and 83.70 % glucose yield with the TDES pretreated willow. Overall, this study demonstrated an effective solvent fractionation approach to maximize the utilization of total lignocellulose under mild conditions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Chemoselective hydrodeoxygenation (HDO) of lignin derivatives is of great importance in converting biomass into high value-added chemicals. Herein, we report a simple hydrothermal pathway to fabricate a highly active, chemically selective, and reusable catalyst (Cu/DMSN) by loading copper clusters on "dendritic" mesoporous silica nanospheres. Cu/DMSN exhibits exceptional catalytic activity (conversion > 99 %, selectivity > 99 %) in the HDO of vanillin toward 2-methoxy-4-methylphenol under mild conditions (140 °C, 0.5 MPa, 3 h), along with good scalability and a wide range of substrates. The excellent catalytic performance can be owed to the combination of suitable acid site and more exposed metal site. This study provides a new strategy for designing supported metal catalysts for hydrodeoxidation of biomass and its derivatives., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The presence of refractory lignocellulose presents a significant challenge in green waste (GW) composting. This research applied both a conventional iron-based Fenton-like process (with a Fenton-like reagent composed of 1.0 % Fe 3 O 4 nanoparticles and 1.0 % H 2 O 2 ) and three modified iron-based Fenton-like processes (with a Fenton-like reagent composed of 1.0 % Fe 3 O 4 nanoparticles and 1.0 % oxalic acid/1.0 % sodium percarbonate/0.5 % Phanerochaete chrysosporium) in GW composting to systematically assess their impacts on lignocellulose degradation during GW composting. The results revealed that iron-based Fenton-like process modified sodium percarbonate exhibited the most significant effects on lignocellulose degradation. Compared with control, degradation rates for lignin, cellulose, and hemicellulose increased by 49.8 %, 39.3 %, and 26.2 % (p < 0.05), respectively. Furthermore, this process enhanced the relative abundance of bacterial communities linked to lignocellulose degradation, particularly Firmicutes and Bacteroidota. These findings offer valuable insights into optimizing GW composting, understanding reactive oxygen species dynamics, and the application of iron-based Fenton-like process., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

As millions of tons of kraft lignin are being wasted, a potential application is to use its crosslinking reactions to build thermosetting bio adhesives. However, the crosslinking reactions between lignin molecules are not fully understood. The present study aims to elucidate the crosslinking reactions of the model lignin compound guaiacylglycerol-β-guaiacyl ether (GGE) via one-step hydroxymethylation/ amination with formaldehyde and diethylenetriamine (DETAM), or one-step glyoxylation/ amination with glyoxal and DETAM via liquid NMR techniques such as 1 H NMR, 13 C NMR, 2D 1 H- 13 C, and 1 H- 15 N HSQC NMR. Specifically, the 2D 1 H- 13 C HSQC NMR spectra confirm the presence of -CH 2 -NH- with a chemical shift of 1 H 2.6-3.6/ 13 C 40-60 ppm, and the formation of methylene linkages via the crosslinking reaction. Also, the 2D 1 H- 15 N HSQC NMR spectra clearly detect the formation of amide and imine bonds at 1 H 7.8/ 15 N 110 and 1 H 8.07/ 15 N 121.5 ppm from the crosslinked GGE., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Biomass-derived carbon quantum dots (CQDs) have the advantage of being green and low-cost, but their complex structure makes the study of their formation mechanism encounter a bottleneck. Lignin-derived CQDs were prepared by a two-step process of "low-temperature liquid depolymerization" coupled with "hydrothermal reaction" in a mild organic acid system. In the first step of the low-temperature acidolysis process, the lignin polymer first undergoes deethering and depolymerization reactions. During the hydrothermal process in the second step, the organic small molecules on the surface of the supernatant are enriched with reactive groups that are dehydrated, condensed, crosslinked, and carbonized under high temperature and pressure to form CQDs. On the other hand, these activated large sp 2 carbon domains in the oxidized solid residue from lignin acidolysis undergo hydrothermal cleavage under high-temperature and high-pressure conditions, followed by deoxygenation and eventual decomposition into small carbon domain CQDs products. Among them, the supernatant component C1 after lignin acidolysis with abundant N-H and C-OH reactive groups is targeted as a key precursor for the formation of lignin-derived CQDs, and the resulting CQDs have both the highest QY (19.5%) and yield (16.5%). This study bridges the research gap on the formation mechanism of biomass-derived CQDs and offers a reference for the sustainable preparation of biomass-derived CQDs., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Dekui Shen reports financial support was provided by National Natural Science Foundation of China. Dekui Shen reports financial support was provided by Key Research & Development Program of Jiangsu Province. Dekui Shen reports financial support was provided by Postgraduate Research & Practice Innovation Program of Jiangsu Province from the Education Department of Jiangsu., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Sugarcane bagasse (SCB) has a recalcitrant structure, which hinders its component dismantling and subsequent high value utilization. Some organic solvents are favorable to dismantle lignocellulose, but their high viscosity prevents separation of components and reuse of solvents. Herein, ethylene glycol phenyl ether (EGPE)-acid system is used as an example to develop green and efficient methods to dismantle SCB, purify polysaccharides and lignin, and reuse solvents. Results show that dismantling SCB at 130 °C, 0.5 % H 2 SO 4 , and 100 min can obtain 85.5 % cellulose recovery, 94.1 % hemicellulose removal and 83.7 % lignin removal. Different molecular weight saccharides are separated by membranes filtration and centrifugation, and lignin recovered by antisolvent precipitation. The solvent recovered by distillation, achieving high dismantling efficiency of 89.2 % cellulose recovery, 94.1 % hemicellulose removal and 94.4 % lignin removal after four recycles. Results show a promising approach for the closed-loop process of dismantling lignocellulose, fractionating saccharides, and reusing solvents in high-viscosity systems., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Biomass pretreatment and conversion are crucial for sustainable development, but lack information on equipment that ensures effective mass transfer and easy biomass separation post-process. This work introduces a novel basket reactor with a stationary bed (StatBioChem) for biomass processing using deep eutectic solvents (DESs). We compared the delignification efficiencies of soft and hard biomass samples processed in the StatBioChem reactor, a stirred tank reactor (STR), and a commercial SpinChem® reactor. The StatBioChem design allowed DES to flow evenly through biomass in the basket, achieving the highest delignification degree, particularly for hard biomass. This effect was not observed in the SpinChem® basket reactor. High delignification led to increased glucose yields in subsequent enzymatic hydrolysis. The StatBioChem effectively combines the simplicity and efficiency of an STR with the ease of solvent recovery typical of basket reactors., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Katarzyna Szymanska reports financial support was provided by National Science Centre of Poland. Katarzyna Szymanska has patent issued to Silesian University of Technology. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

As the most abundant renewable carbon source, lignocellulose holds potential as a raw material for biofuels and biochar. The components required for biofuel production differ from those for biochar, so combining processes can reduce costs. Biofuel preparation necessitates cellulase treatment of lignocellulose. This study examines the effects of various enzyme treatment conditions (dosage, time, temperature) on lignocellulose, focusing on the properties of biochar derived from it (BC-SR). A mathematical model was constructed to study the relationship between enzyme treatment conditions and BC-SR properties. BC-SR exhibited high adsorption selectivity for bisphenol A and outperformed untreated biochar in fixed-bed column experiments, demonstrating greater removal efficiency and structural integrity. This study provides insights into the impact of enzymatic treatment on biochar and offers a cost-effective method for producing stable, efficient biochar. Additionally, a highly persistent biochar can enter the carbon trading market as a carbon-neutral technology, further realizing economic and environmental benefits., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Recently, the growing health awareness of society on the utilization of fabrics has led to an increasing demand for natural-based antibacterial textiles. Lignin, a generous polyphenol compound in nature, is capable of preventing bacterial growth; in particular, it dwells bacteria closely together on human skin, such as Staphylococcus epidermidis, Bacillus subtilis, Propionibacterium acnes, and Staphylococcus aureus. However, the antibacterial properties of lignin are limited by factors such as the lignin concentration, source, and type of bacteria. This study aimed to evaluate the potency of lignin as an antibacterial agent for textiles. Moreover, the thermal properties and wettability of the textile after lignin coating were also investigated. This study showed that lignin isolation methods significantly contributed to the inhibition of bacterial growth in the clear zone diameter. In addition, the lignin structure, lignin concentration, and type of bacteria had notably different antibacterial effects. SEM images showed that lignin was successfully coated on the fiber, and the antibacterial textile was successfully fabricated with clear zones in the range of 0.1-0.5 cm against four different bacteria. Lignin did not significantly improve the thermal stability of the textile, as proven by the TGA results. After the HDTMS coating by dispersion method, the wettability of the lignin-textile improved to that of the hydrophobic material, with a contact angle greater than 119.05° with excellent antibacterial properties (clear zone of 0.1-0.43 cm)., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Cotreatment, mechanical disruption of lignocellulosic biomass during microbial fermentation, is a potential alternative to thermochemical pretreatment as a means of increasing the accessibility of lignocellulose to biological attack. Successful implementation of cotreatment requires microbes that can withstand milling, while solubilizing and utilizing carbohydrates from lignocellulose. In this context, cotreatment with thermophilic, lignocellulose-fermenting bacteria has been successfully evaluated for a number of lignocellulosic feedstocks. Here, cotreatment was applied to sugarcane bagasse using monocultures of the cellulose-fermenting Clostridium thermocellum and cocultures with the hemicellulose-fermenting Thermoanaerobacterium thermosaccharolyticum. This resulted in 76 % carbohydrate solubilization (a 1.8-fold increase over non-cotreated controls) on 10 g/L solids loading, having greater effect on the hemicellulose fraction. With cotreatment, fermentation by wild-type cultures at low substrate concentrations increased cumulative product formation by 45 % for the monoculture and 32 % for the coculture. These findings highlight the potential of cotreatment for enhancing deconstruction of sugarcane bagasse using thermophilic bacteria., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Lee R. Lynd is a shareholder in a start-up company focusing on cellulosic biofuel production and conversion. The authors declare that they have no other competing financial interest or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

In this manuscript, three components of lignocellulosic biomass were obtained by deconstructing bamboo with γ-valerolactone-H 2 O biphasic system, and the delignification rate of 80.92 % was achieved at 120 °C for 90 min. Lignin nanospheres with diameters ranging from 75 nm to 2 um could be customized by varying the self-assembly rate. Furthermore, the lignin nanospheres-poly(vinyl alcohol) film was prepared by cross-linking lignin nanospheres and poly(vinyl alcohol), which can obtain 90 % ultraviolet absorption capacity, while the light transmittance in non-ultraviolet band was almost unchanged. At the same time, due to the strong hydrogen formation between lignin nanospheres and poly(vinyl alcohol) bond network, the tensile properties of the composite film were also improved by 30 %. Besides, the high specific surface area of biomass-derived porous biochar (2056 m 2 /g) can be obtained after carbonization of solid residues at 850 °C for 2 h, which was almost 8 times the specific surface area of the direct biomass carbonization due to the removal of lignin and hemicellulose. biomass-derived porous biochar can be used as an adsorbent, with a CO 2 capture capacity of 4.5 mmol g -1 at normal temperature (25 °C, 1 bar). The filtrate after the reaction contained a large amount of hemicellulose oligomers, which can be reacted with dichloromethane at 170 °C for 1 h to obtain the furfural yield of 74 %. In summary, the proposed biorefinery scheme achieves a full-component upgrade of lignocellulose and can be further applied in various downstream fields., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Lignocellulosic biomass, renewable with short growth cycle and diverse sources, can be substituted fossil fuel. However, low effective hydrogen-to-carbon ratio (H/C eff ) limits its applications. Torrefaction and co-pyrolysis with high H/C eff feedstocks are promising technology. This paper investigated the effect of heating modes on oil-bath torrefaction of walnut shells, followed by fast co-pyrolysis. Six heating modes during oil-bath torrefaction were evaluated. Com1 (Microwave 67 %, Lightwave 33 %) yielded the lowest residual yield 84 wt%, while the highest gas production 495.47 mL/g which mainly composed of CO and CO 2 . Torrefied feedstock under Com1 had the highest H/C eff . Decarboxylation and decarbonylation reactions dominated among oil-bath torrefaction. Com1 produced the most hydrocarbons and least oxygen-containing compounds. As microwave ratio decreased, the content of olefins, acids and phenols decreased, monocyclic aromatic hydrocarbons and alcohols was showed opposite tend. This study offers new ideas for microwave and lightwave torrefaction and promoting hydrocarbon production from lignocellulosic biomass., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Lignocellulose presents a promising alternative to fossil fuels. Monitoring the mass and size changes of lignocellulosic particles without disrupting the process can assist in adjusting pretreatment and enzymatic hydrolysis, where conventional sieving methods fall short. A method utilizing focused beam reflectance measurement (FBRM) was developed to establish mathematical correlations between FBRM chord information (chord length and count) and particle characteristics (weight and size) quantified through sieving. Results indicate particle size exhibits a linear correlation with the square weighted median chord length (L sqr ) with R 2 at 0.93. Further, real-time bulk particle mass can be predicted using L sqr and chord count (R 2 0.98). These correlations are applicable in range 53 μm to 358.5 μm. Real-time monitoring of enzymatic hydrolysis of corn stalks has demonstrated the practical applicability of FBRM. This study introduces a novel approach for online characterization of lignocellulosic particles, thereby enhancing lignocellulosic biorefineries., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Thermochemical treatment is significantly impacted by the physiochemical properties of lignocellulosic biomass. Traditional characterization methods lack granularity, requiring advanced analytical techniques for comprehensive biomass characterization. This study analyzed elemental composition and their distribution in untreated rice husk, rice straw, and bamboo chips at micron and sub-micron scales. Results reveal significant variations in composition and spatial distribution of metallic components among agro-residues. Thermogravimetric analysis shows divergent decomposition patterns, while spectroscopic analysis indicates structural complexities and distinct silica content. Surface mapping illustrates prevalent silica and alkali metals on rice husk and rice straw. Atomic force microscopy depicts distinctive surface morphologies, with rice straw exhibiting heightened roughness due to silica bodies. Inductively coupled plasma-mass-spectrometry identified the abundance of alkali and alkaline earth metals in rice waste. Time-of-flight secondary ion mass spectrometry elucidates elemental spatial localization, affirming heterogeneous distribution across rice waste and homogenous distribution across bamboo waste. This study bridges the gap between biomass composition and optimized thermochemical conversion outcomes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Freeze pretreatment combined with alkaline-hydrothermal method of rice straw for enzymatic hydrolysis was studied. Crystallization stress in the rice stem pores caused by water freezing at -20- -40 °C was modeled to illustrate the destruction mechanism. The stress was calculated as 22.5-38.3 MPa that were higher than the tensile yield stress of untreated stems (3.0 MPa), indicating ice formation damaging pore structure. After freeze at -20 °C, rice straw was further hydrothermally treated at 190 °C with 0.4 M Na 2 CO 3 , achieving 72.0 % lignin removal and 97.2 % cellulose recovery. Glucose yield rose to 91.1 % by 4.3 times after 24 h hydrolysis at 10 FPU loading of Cellic®CTec2 cellulase. The specific surface area of rice straw was 2.6 m 2 /g increased by 1.2 times after freeze. Freeze combined with alkaline-hydrothermal treatment is a green and energy-efficient method for improving enzymatic hydrolysis., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The constant ammonia gas (NH 3 ) and greenhouse gases (GHG) emissions were considered as a deep-rooted problem in composting which caused air pollution and global climate change. To achieve the mitigation of NH 3 and GHG, a novel additive derived from wasted straw, with modified structure and functional groups, has been developed. Results showed that the adsorption capacity of modified lignin (ML) for both ammonium and nitrate was significantly increased by 132.5-360.8 % and 313.7-454.3 % comparing with biochar (BC) and phosphogypsum (PG) after reconstructing porous structure and grafting R-COOH, R-SO 3 H functional groups. The application of ML could reduce 36.3 % NH 3 emission during composting compared with control. Furthermore, the synergetic mitigation NH 3 and GHG in ML treatment resulted in a reduction of global warming potential (GWP) by 31.0-64.6 % compared with BC and PG. These findings provide evidence that ML can be a feasible strategy to effectively alleviate NH 3 and GHG emissions in composting., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The growing interest in utilizing lignin for dye removal has gained momentum, but there is limited information on the intricate relationship between lignin structural characteristics and adsorption efficacy, especially for its biochar derivatives. This study focused on three types of lignin and their corresponding biochar derivatives. Among them, ZnCl 2 -activated acidic/alkali densified lignin preparation of lignin-derived active carbon exhibited superior adsorption performance, achieving 526.32 mg/g for methylene blue and 2156.77 mg/g for congo red. Its exceptional adsorption capacity was attributed to its unique structural properties, including low alkyl and O-alkyl group content and high aromatic carbon levels. Furthermore, the adsorption mechanisms adhered to pseudo-second-order kinetics and the Langmuir model, signifying a spontaneous process. Intriguingly, lignin-derived active carbon also demonstrated remarkable recovery capabilities. These findings provide valuable insights into the impact of structural attributes on lignin and its biochar's adsorption performance., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

This study investigated a lignin-first approach to produce furan-modified lignin from sugarcane bagasse (SB), rice hull (RH), and sunn hemp biomass (SHB) using 5 methylfurfural (MF) and 5 methul-2-furanmethanol (MFM). The reaction time (5 h) was selected based on the delignification of SB using methanol and Ru/C catalyst which yielded the highest hydroxyl content. Delignification of SB with various MF weight ratios (1:1, 1:2, 1:3, 2:1, and 3:1) revealed that 1:1 and 2:1 ratios produced the highest hydroxyl content (7.7 mmol/g) and bio-oil yield (23.2 % wt% total weight). Further exploration identified that RH and MF at 1:1 ratio and SHB and MF at a 2:1 ratio produced the highest hydroxyl content (13.0 mmol/g) and bio-oil yield (31.6 % wt% tot. weight). This study developed a one-step method to extract and modify lignin with furan compounds simultaneously while opening new avenues for developing value-added products., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The cost of detoxification and neutralization poses certain challenges to the development of an economically viable lactic acid biorefinery with lignocellulosic biomass as feedstock. Herein, red mud, an alkaline waste, was explored as both a detoxifying agent and a neutralizer. Red mud treatment of lignocellulosic hydrolysate effectively removed the inhibitors generated in dilute acid pretreatment, improving the lactic acid productivity from 1.0 g/L·h -1 to 1.9 g/L·h -1 in later fermentation. In addition, red mud could replace CaCO 3 as a neutralizer in lactic acid fermentation, which in turn enabled simultaneous bioleaching of valuable metals (Sc, Y, Nd, and Al) from red mud. The neutralization of alkali in red mud by acids retained in lignocellulosic hydrolysate and lactic acid produced from fermentation led to effective dealkalization, rendering a maximum alkali removal efficiency of 92.2 %. Overall, this study offered a win-win strategy for the valorization of both lignocellulosic biomass and red mud., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Lignin, a complex phenolic polymer crucial for plant structure, is mostly used as fuel but it can be harnessed for environmentally friendly applications. This article explores ozonation as a green method for lignin extraction from lignocellulosic biomass, aiming to uncover the benefits of the extracted lignin. A pilot-scale ozonation reactor was employed to extract lignin from Miscanthus giganteus (a grass variety) and vine shoots (a woody biomass). The study examined the lignin extraction and modification of the fractions and identified the generation of phenolic and organic acids. About 48 % of lignin was successfully extracted from both biomass types. Phenolic monomers were produced, vine shoots yielding fewer monomers than Miscanthus giganteus. Ozonation generated homogeneous lignin oligomers, although their molecular weight decreased during ozonation, with vine shoot oligomers exhibiting greater resistance to ozone. Extracted fractions were stable at 200 °C, despite the low molecular weight, outlining the potential of these phenolic fractions., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: AUSSENAC Thierry reports financial support was provided by Hauts-de-France Regional Council. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

A cost-effective, and low-energy room-temperature cascade catalytic carbonization strategy is demonstrated for converting lignin into graphite with a high yield of 87 %, a high surface potential of -37 eV and super-hydrophilicity. This super-hydrophilic feature endows the lignin-derived graphite to be dispersed in a variety of polar solvents, which is important for its future applications. Encapsulating of liquid metals with the graphite for electrical circuit patterning on flexible substrates is also advocated. These written patterns show superb conductivity of 4.9 × 10 6  S/m, offering good performance stability and reliability while being repeatedly stretched, folded, twisted, and bent. This will offer new designs for flexible electronic devices, sensors, and biomedical devices., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Due to the complexity of biomass structures, the conversion of raw biomass into value-added chemicals is challenging and often requires efficient pretreatment of the biomass. In this paper, a simple and green pre-oxidation method, which was conducted under the conditions of 2 wt% H 2 O 2 , 80 min, and 150 °C, was reported to significantly increase the production of levoglucosan (LG) from biomass pyrolysis. The result showed that the LG yield significantly increased from 2.3 wt% (without pre-oxidation) to 23.1 wt% when pine wood was employed as a sample for pyrolysis at 400 °C, resulting from the removal of hemicellulose fraction and the in-situ acid catalysis of lignin carboxyl groups formed during the pre-oxidation. When the conditions for pre-oxidation became harsher than the above, the LG yield reduced because the decomposition of cellulose fraction in biomass. The study supplies an effective method for utilization of biomass as chemicals., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Hardwood kraft lignin from the pulping industry is burned or discarded. Its valorization was conducted by subjecting fractionation, amination with ethylenediamine, diethylenetriamine, and monoethanolamine, and crosslinking with formaldehyde or glyoxal to obtain bio-based wood adhesives. Acetone-soluble and insoluble hardwood kraft lignin were prepared and subjected to amination and then crosslinking. Fourier transform infrared, 13 C NMR, 15 N NMR, and X-ray photoelectron spectroscopy results revealed successful amination with amide, imine, and ether bonds and crosslinking of all samples. Hardwood kraft lignin aminated with diethylenetriamine/ethylenediamine and crosslinked using glyoxal exhibited excellent results in comparison with samples crosslinked using formaldehyde. Acetone-insoluble hardwood kraft lignin aminated and crosslinked using diethylenetriamine and formaldehyde, respectively, exhibited excellent adhesion strength with plywood, satisfying the requirements of the Korean standards. The amination and crosslinking of industrial waste hardwood kraft lignin constitute a beneficial valorization method., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Poplar is widely used in the paper industry and accompanied by abundant branches waste, which is potential feedstock for bioethanol production. Acid-chlorite pretreatment can selectively remove lignin, thereby significantly increasing enzymatic efficiency. Moreover, lignin residues valorization via gasification-syngas fermentation can achieve higher fuel yield. Herein, environmental and economic aspects were conducted to assess technological routes, which guides further process optimization. Life cycle assessment results show that wood-based biorefineries especially coupling scenarios have significant advantages in reducing global warming potential in contrast to fossil-based automotive fuels. Normalization results indicate that acidification potential surpasses other indicators as the primary impact category. In terms of economic feasibility, coupling scenarios present better investment prospects. Bioethanol yield is the most critical factor affecting market competitiveness. Minimum ethanol selling price below ethanol international market price is promising with higher-levels technology. Further work should be focused on technological breakthrough, consumable reduction or replacement., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The primary objective of this study is to explore the application of a deep eutectic solvent, synthesized from lactic acid and choline chloride, in combination with a pre-treatment involving ZSM-5 catalytic fast pyrolysis, aimed at upgrading the quality of bio-oil. Characterization results demonstrate a reduction in lignin content post-treatment, alongside a significant decrease in carboxyls and carbonyls, leading to an increase in the C/O ratio and noticeable enhancement in crystallinity. During catalytic fast pyrolysis experiments, the pre-treatment facilitates the production of oil fractions, achieving yields of 54.53% for total hydrocarbons and 39.99% for aromatics hydrocarbons under optimized conditions. These findings validate the positive influence of the deep eutectic solvent pre-treatment combined with ZSM-5 catalytic fast pyrolysis on the efficient production of bio-oil and high-value chemical derivatives. ., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Lignin utilization in value-added co-products is an important component of enabling cellulosic biorefinery economics. However, aqueous dilute acid pretreatments yield lignins with limited applications due to significant modification during pretreatment, low solubility in many solvents, and high content of impurities (ash, insoluble polysaccharides). This work addresses these challenges and investigates the extraction and recovery of lignins from lignin-rich insoluble residue following dilute acid pretreatment and enzymatic hydrolysis of corn stover using three extraction approaches: ethanol organosolv, NaOH, and an ionic liquid. The recovered lignins exhibited recovery yields ranging from 30% for the ionic liquid, 44% for the most severe acid ethanol organosolv condition tested, and up to 86% for the most severe NaOH extraction condition. Finally, the fractional solubilities of different recovered lignins were assessed in a range of solvents and these solubilities were used to estimate distributions of Hildebrand and Hansen solubility parameters using a novel approach., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

In this article we can observe the scanning by the literature for the pretreatment of steam explosion applied to lignocellulose biomass. A comparison of the chemical and physical characterization of potato peel as a lignocellulose biomass. Besides, the innovative design of a continuous reactor for the potato peel steam explosion process is shown, with specific temperature and pressure conditions on a pilot scale, detailing its parts. Finally, a finite element analysis was performed where stress results were obtained from the reactor material, severity factor, structural analysis and thermal analysis, providing a panorama of the reactor's behavior with the conditions specific., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Carlos Guerrero reports financial support was provided by Colombia Ministry of Science Technology and Innovation. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Deep eutectic solvents (DESs) offer a potential opportunity in biomass utilization industries. This work emphasized the impact of hydrogen bond donors (HBD) and acceptors (HBA) on deconstruction and valorization of rice straw. Acidity, alkyl chain length, hydrogen bonding ability and functional groups of HBD and HBA appeared to be important factors affecting the fractionated pulps and lignins, which further influenced ethanol fermentation. Among the candidate DESs, lactic acid/guanidine hydrochloride (LGH) was proved to be the most suitable one due to the excellent delignification and xylan removal. For the downstream fermentation process, 0.47 g g -1 of bioethanol with 0.55 g/L h -1 of productivity can be obtained from the LGH pulp's hydrolysate. Mass balance showed 302.8 g bioethanol and 119.0 g technical lignin can be co-generated from 1 kg dried rice straw. This "green" valorization strategy offers a promising scheme in biorefinery of lignocelluloses., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Applications of deep eutectic solvent (DES) systems to separate lignocellulosic components are of interest to develop environmentally friendly processes and achieve efficient utilization of biomass. To enhance the performance of a binary neutral DES (glycerol:guanidine hydrochloride), various Lewis acids (e.g., AlCl 3 ·6H 2 O, FeCl 3 ·6H 2 O, etc.) were introduced to synthesize a series of ternary DES systems; these were coupled with microwave heating and applied to moso bamboo. Among the ternary DES systems evaluated, the FeCl 3 -based DES effectively removed lignin (81.17%) and xylan (85.42%), significantly improving enzymatic digestibility of the residual glucan and xylan (90.15% and 99.51%, respectively). Furthermore, 50.74% of the lignin, with high purity and a well-preserved structure, was recovered. A recyclability experiment showed that the pretreatment performance of the FeCl 3 -based DES was still basically maintained after five cycles. Overall, the microwave-assisted ternary DES pretreatment approach proposed in this study appears to be a promising option for sustainable biorefinery operations., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

An effective deep eutectic solvent (DES) and Iron(III) chloride (FeCl 3 ) combination pretreatment system was developed to improve the removal efficiency of lignin and hemicellulose from corn stover (CS) and enhance its saccharification. N-(2-hydroxyethyl)ethylenediamine (NE) was selected as the hydrogen-bond-donor for preparing ChCl-based DES (ChCl:NE), and a mixture of ChCl:NE (60 wt%) and FeCl 3 (0.5 wt%) was utilized for combination pretreatment of CS at 110 ℃ for 50 min. FeCl 3 /ChCl:NE effectively removed lignin (87.0 %) and xylan (55.9 %) and the enzymatic hydrolysis activity of FeCl 3 /ChCl:NE-treated CS was 5.5 times that of CS. The reducing sugar yield of pretreated CS was 98.6 %. FeCl 3 /ChCl:NE significantly disrupted the crystal structure of cellulose in CS and improved the removal of lignin and hemicellulose, enhancing the conversion of cellulose and hemicellulose into monomeric sugars. Overall, this combination of FeCl 3 and DES pretreatment methods has high application potential for the biological refining of lignocellulose., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

A novel efficient pretreatment system containing alkaline deep eutectic solvent (DES) and tetrahydrofuran (THF) was developed in the present study. Under pretreatment conditions of 160 ℃ and 1 h, DES-THF pretreatment was more efficient (81.61%) in cellulose digestibility improvement than DES (choline chloride/monoethanolamine, 67.54%). To further explore lignin structural transformation and lignin-cellulase interaction after pretreatment, milled wood lignin (MWL) was extracted and characterized. Compared with DES-MWL, DES-THF-MWL showed an increased carboxyl group content (24.0%) and decreased condensed phenolic hydroxyl content (9.1%). In DES-MWL, β-O-4 content was 21.79%, while in DES-THF-MWL, β-O-4 accounted for 45.45%, indicating that the addition of THF alleviated cleavage of β-O-4 alkyl ether bonds. Fluorescence emission spectroscopy results showed that quenching mechanism of DES-THF-MWL and cellulase was dynamic, which was different from other lignin. Compared with DES-MWL, decreased K a between DES-THF-MWL and cellulase indicated decreasing interaction between them. DES-THF pretreatment provides a novel pretreatment method for bioenergy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

Major challenge in biorefineries is the use of all lignocellulosic components, particularly lignins. In this study, Thermobacillus xylanilyliticus grew on kraft lignin, steam-exploded and native wheat straws produced different sets of phenoloxidases and xylanases, according to the substrate. After growth, limited lignin structural modifications, mainly accompanied by a decrease in phenolic acids was observed by Nuclear Magnetic Resonance spectroscopy. The depletion of p-coumaric acid, vanillin and p-hydroxybenzaldehyde combined to vanillin production in the culture media indicated that the bacterium can transform some phenolic compounds. Proteomic approaches allowed the identification of 29 to 33 different hemicellulases according to the substrates. Twenty oxidoreductases were differentially expressed between kraft lignin and steam-exploded wheat straw. These oxidoreductases may be involved in lignin and aromatic compound utilization and detoxification. This study highlights the potential value of Thermobacillus xylanilyticus and its enzymes in the simultaneous valorization of hemicellulose and phenolic compounds from lignocelluloses., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

The productive separation and conversion of corn straw offers significant prospects for the economic viability of biorefineries centered on straw resources. In this work, a graded utilization method was proposed to produce xylo-oligosaccharides (XOS), ethanol and lignin from corn straw by nicotinic acid (NA) hydrolysis and water/pentanol pretreatment. A XOS yield of 52.6 % was achieved under optimized conditions of 100 mM NA, 170 °C and 30 min. The solid residue was directly treated with water/pentanol, achieving a lignin removal rate of 79.7 %, and the total XOS yield was improved to 62.6 %. The lignin recovered from pentanol had a high purity of 97.6 %, with high phenolic OH content. Simultaneous saccharification and fermentation of final residue resulted in an ethanol yield of 92.0 %, which yielded 55.3 g/L ethanol. Thus, NA hydrolysis and water/pentanol pretreatment provided an efficient, environmentally friendly approach to fractionate corn straw for the co-production of XOS, ethanol, and lignin., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Lignin is the most abundant natural aromatic macromolecule in the nature, but its high value-added utilization has been seriously hindered by the highly random and branched structures and the high difficulty in separation and purification. A microwave-assisted ternary deep eutectic solvent (DES) composed by formic acid, lactic acid and choline chloride was developed for lignin pretreatment. The effects of three types of DES on main characteristics of lignin were investigated, and the corresponding dissolution mechanism was proposed. The results showed that, the microwave-assisted ternary DES pretreatment showed an obvious improvement on main characteristics of regenerated lignin, e.g., a higher purity, lower molecular weight with reduced dispersity, improved thermal stability, higher phenolic hydroxyl content, and increased antioxidative activity in comparison with control. It is expected that the lignin macromolecular can be facile regulated and upgraded by the proposed ternary DES., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The study reports the economic and sustainable syntheses of a lignin-based porous carbon (LPC) for CO 2 capture application. The pH values of hydrothermal solution affected the polymerization and aromatization of spheroidization, with morphological changes from blocky to microsphere. In addition, the reliable mechanisms of CO 2 adsorption were proposed by combining experiments with Gaussian16 simulations based on DFT. The electrostatic attraction of oxygen-containing functional groups and the diffusivity resistance of CO 2 in the pores are the key factors for the CO 2 adsorption. ​The carboxyl groups have the strongest electrostatic attraction to CO 2 . LPC-pH 1 has the highest carboxyl group content, possessing a CO 2 adsorption capacity of up to 5.10 mmol/g at 0℃, 1 bar. Furthermore, CO 2 diffusion resistance became a main factor as the adsorption temperature increases. The innovative combination of quantum chemical calculations and microscopic properties provides a viable pathway for an insight into the future control of lignin-based carbon formation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The biochemical methane potential test is a standard method to determine the biodegradability of lignocellulosic wastes (LWs) during anaerobic digestion (AD) with disadvantages of long experiment duration and high operating expense. This paper developed a machine learning model to predict the cumulative methane yield (CMY) using the data of 157 LWs regarding physicochemical characteristics, digestion condition and methane yield, with the coefficient of determination equal to 0.869. Model interpretability analyses underscored lignin content, organic loading, and nitrogen content as pivotal attributes for CMY prediction. For the feedstocks with a cellulose content exceeding about 50%, the CMY in the early AD stage would be relatively lower than those with low cellulose content, but prolonging digestion time could promote methane production. Besides, lignin content in feedstock surpassing 15% would significantly inhibit methane production. This work contributes to valuable guidance for feedstock selection and operation optimization for AD plants., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

In this study, a surfactant-assisted diluted ethylenediamine (EDA) fractionation process was investigated for co-generation of technical lignin and biobutanol from corn stover. The results showed that the addition of PEG 8000 significantly enhanced cellulose recovery (88.9 %) and lignin removal (68.9 %) in the solid fraction. Moreover, the pulp achieved 86.5 % glucose yield and 82.6 % xylose yield in enzymatic hydrolysis. Structural characterization confirmed that the fractionation process promoted the preservation of active β-O-4 bonds (35.8/100R) in isolated lignin and functionalized the lignin through structural modification using EDA and surfactant grafting. The enzymatic hydrolysate of the pulps yielded a sugar solution for acetone-butanol-ethanol (ABE) fermentation, resulting in an ABE concentration of 15.4 g/L and an overall yield of 137.2 g/Kg of dried corn stalk. Thus, the surfactant-assisted diluted EDA fractionation has the potential to enhance the overall economic feasibility of second-generation biofuels production within the framework of biorefinery., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Laccase-like multicopper oxidases are recognized for their potential to alter the reactivity of lignins for application in value-added products. Typically, model compounds are employed to discover such enzymes; however, they do not represent the complexity of industrial lignin substrates. In this work, a screening pipeline was developed to test enzymes simultaneously on model compounds and industrial lignins. A total of 12 lignin-active fungal multicopper oxidases were discovered, including 9 enzymes active under alkaline conditions (pH 11.0). Principal component analysis revealed the poor ability of model compounds to predict enzyme performance on industrial lignins. Additionally, sequence similarity analyses grouped these enzymes with Auxiliary Activity-1 sub-families with few previously characterized members, underscoring their taxonomic novelty. Correlation between the lignin-activity of these enzymes and their taxonomic origin, however, was not observed. These are critical insights to bridge the gap between enzyme discovery and application for industrial lignin valorization., Competing Interests: Declaration of competing interest The authors have no competing interests to declare., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

In this study, a combined pretreatment involving autohydrolysis and p-toluenesulfonic acid (p-TsOH) was performed on poplar to coproduce xylooligosaccharides (XOSs) and monosaccharides. The autohydrolysis (180 °C, 30 min) yielded 53.2 % XOS and enhanced the delignification efficiency in the subsequent p-TsOH treatment. Furthermore, considerably high glucan contents (64.1 %∼83.1 %) were achieved in the combined pretreated substrates. However, their enzymatic digestibilities were found to be extremely poor (9.6 %∼14.2 %), which were even lower than the single p-TsOH pretreated substrates (10.2 %∼35.8 %). The underlying reasons were revealed by systematically investigating the effects of the single and combined pretreatment strategies on substrate properties. Moreover, the Tween 80 addition successfully reversed the adverse effects of combined pretreatment on the enzymatic hydrolysis, achieving a high glucose yield of 99.3 % at an enzyme loading of 10 filter paper units/g (FPU/g) glucan. These results deepen the understanding of the synergy of combined pretreatment on biomass fractionation and enzymatic saccharification., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The enzymatic efficiency of β-glucosidases is influenced by their binding behavior onto insoluble substrates (cellulose and lignin) during bioconversion of lignocellulose. This study suggested that the Bgl3 protein (Aspergillus fumigatus) showed strong adsorption affinity to lignin and the Bgl1 protein (Penicillium oxalicum) tended to adsorb to cellulose. It indicated that the various surface properties of the fibronectin type Ш-like domain (FnIII) led to different binding properties of β-glucosidases by investigating their binding mechanism. By engineering β-glucosidases' FnIII domain, Bgl3-1 and Bgl1-3 were constructed, which both showed lower binding capacities to insoluble substrates. As well as for Bgl1-3, its sensitivity to the phenolic component was also eased. Based on that, the reconstructed protein showed high catalytic efficiency during the enzymatic hydrolysis of corn stover by effectively transforming cellobiose to glucose. Thus, this study provided a new strategy to engineer β-glucosidases to enhance their performance in the cellulase system., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Corn, rice, wheat, and sugar are major sources of food calories consumption thus the massive agricultural waste (AW) is generated through agricultural and agro-industrial processing of these raw materials. Biological conversion is one of the most sustainable AW management technologies. The abundant supply and special structural composition of cellulose, hemicellulose, and lignin could provide great potential for waste biological conversion. Conversion of hemicellulose to xylitol, cellulose to ethanol, and utilization of remnant whole cells biomass to synthesize phenylacetylcarbinol (PAC) are strategies that are both eco-friendly and economically feasible. This co-production strategy includes essential steps: saccharification, detoxification, cultivation, and biotransformation. In this review, the implemented technologies on each unit step are described, the effectiveness, economic feasibility, technical procedures, and environmental impact are summarized, compared, and evaluated from an industrial scale viewpoint., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

High-solids enzymatic hydrolysis for biomass has currently received considerable interest. However, the solid effect during the process limits its economic feasibility. This work presented an ordered polyethylene glycol (PEG) pre-incubated strategy for enhancing the auxiliary effect of PEG in a high-solids enzymatic hydrolysis system. The substrate and enzyme were separately pre-incubated with PEG in this strategy. The ordered PEG pre-incubated strategies yielded a maximum glucose concentration of 166.6 g/L from 32 % (w/v) pretreated corncob with an enzymatic yield of 94.1 % by 72 h hydrolysis. Using this method, PEG not only lessened the lignin adsorption to cellulase but also altered particle rheological characteristics in the high-solids enzymatic hydrolysis system as a viscosity modifier. This study offered a new insight into the mechanism behind the PEG synergistic effect and would make it possible to achieve efficient high-solids loading hydrolysis in the commercial manufacture of cellulosic ethanol., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)