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It is still a challenge to find an effective solvent system that can simultaneously dissolve the cellulose and lignin in biomass residues to fabricate lignocellulose hydrogels (LHs). Herein, corncob residues from furfural production were pretreated with alkaline peroxide to regulate the lignin content. The lignin/cellulose composites with various lignin content were then dissolved and regenerated by a green and facile ZnCl

Green and low cost deep eutectic solvents (DESs) are promising to replace the solid acids and ionic liquids in biomass fractionation process. To enhance the lignocellulose pretreatment efficiency, an acidic DES that composed of Brønsted acid (ZnCl

The feasibility of high-solids simultaneous saccharification and ethanol production was investigated using unwashed corncob residues (CRs) with tea-seed cake (TSC). Tea saponin of TSC could serve as an accelerant to enhance ethanol production and reduce the dosage of enzymes. The proteins of TSC could be the nitrogen resource for yeast. The effects of substrate concentration (10%, 15%, and 20% (w/w)), enzyme dosage (2.5–15 FPU/g-cellulose), and types of media on ethanol production were evaluated. An ethanol yield of 86.56% of the theoretical maximum could be obtained at a substrate concentration of 15% (w/w) with 10 FPU/g-cellulose. Furthermore, fermentations in different media showed that the surface tension (49.21 mN/m) and contact angle (42.6°) of the fermentation system with TSC were lower than those from the other systems. This study found that adding TSC to the fermentation system was an attractive strategy to achieve high ethanol yield without any pretreatment. Comprehensive utilization of CRs and TSC as feedstocks for ethanol production can reduce the cost of biorefineries with environmental benefits.

Metal-organic frameworks (MOFs) could serve as efficient matrixes to immobilize cellulase because of their high stability and porous morphology. Herein, the Zr-based MOFs (UiO-66 and UiO-66-NH2) assisted 20 wt% high-solids hydrolysis of untreated corncob residues (CRs) at low enzyme loading was investigated. Glucan hydrolysis yields increased to 60.55% and 71.47% by separately adding 4 g/L UiO-66 and UiO-66-NH2 at 5 FPU/g-glucan cellulase dosage. The maximum hydrolysis yield reached 90.01% at 10 FPU/g-glucan in the presence of 4 g/L UiO-66-NH2. Analysis of free protein concentration and cellulase activity suggested that MOFs effectively increased cellulase catalytic activity and stability, thus boosted CRs enzymatic hydrolysis efficiency. Additionally, UiO-66-NH2 immobilization gave a high catalytic activity because of the abundant anchor sites of NH2 groups. This research presents the promising future of MOFs’ application in lignocellulosic biomass bioconversion and other areas requiring immobilized enzymes.

Wood-based solar desalination is emerged as one of the promising methods to address the water shortage problem. Herein, a wood evaporator was designed by a two-layer structure: a hydrophobic top layer (Fe3O4) and a superhydrophilic delignified wood bottom layer. The Fe3O4 coated delignified wood (Fe-D-Wood) demonstrates an evaporation rate of 1.3 kg m−2 h−1 and a conversion efficiency of 73%. Fe3O4 with a narrow bandgap (0.8 eV) affords a broad light absorption and polyvinyl alcohol (PVA) enhances the affinity between Fe3O4 and wood substrate, and the wood evaporator presents a good anti-fouling property. Two reasons contribute to such self-regenerating ability: i) salts are difficult to deposit on the hydrophobic layer, and ii) the rapid water uptake promotes the re-dissolution of salts into bulk water. Such wood-based evaporator holds great potential for practical desalination applications.

Although great progress has been made in the research on conversion of cellulosic ethanol, the high conversion cost still exists as an obstacle. Thus, various measures such as reducing the chemical usage, minimizing the enzyme loading, and decreasing the energy consumption are required to lower the cost. Adding surfactants in bioethanol production process is recognized as a simple, effective, and economical strategy to enhance the fermentable sugars production. Therefore, making full use of surfactants (e.g., natural saponin from agricultural and forestry wastes and lignosulfonate) and other industrial wastes in the production of cellulosic ethanol would bring significant economic and environmental benefits. In this review, the recent progress on the application of different types of surfactants (synthetic, natural, and biosurfactant) in cellulosic ethanol production was summarized. The possible mechanism by surfactants was explored. The challenges of current research and outlook of surfactants used in the bioconversion of lignocellulosic biomass were also discussed.

Co-production of glucose, furfural and other green materials based on a lignocellulosic biorefinery is a promising way to realize the commercial application of corncob residues. An effective process was developed for glucose production using low temperature bisulfite pretreatment and high-solids enzymatic hydrolysis. Corncob residues from furfural production (FRs) were pretreated with 0.1g NaHSO3/g dry substrate at 100°C for 3h. Lignin was sulfonated and sulfonic groups were produced during pretreatment, which resulted in decreasing the zeta potential of the samples. Compared with raw material, bisulfite pretreatment of FRs increased the glucose yield from 18.6 to 99.45% after 72h hydrolysis at a solids loading of 12.5%. The hydrolysis residues showed a relatively high thermal stability and concentrated high derivatives. Direct pretreatment followed by enzymatic hydrolysis is an environmentally-friendly and economically-feasible method for the production of glucose and high-purity lignin, which could be further converted into high-value products.

Advanced high strength steels (AHSS) are used more and more in automotive industry for increasing crashworthiness and weight reduction. Improving metal flow and reduce friction are important to forming the part and decrease part reject rates of AHSS. The present study focused on friction characteristics and drawbead restraining force of Dual Phase (DP) steels with or without coating, such as DP980, DP780, DP590, DP780+Z, DP780+ZF, DP590+Z, using experimental approach. The effect of material properties, temperature, sliding velocity, surface roughness, dry and lubricant on friction behavior of DP steels is investigated. The contrast of DP steels with mild IF steel is carried out. The restraining force draw through different radius of drawbead is evaluated. This study is benefit to the set up of technique parameters during sheet metal forming simulation.

Background As the most abundant renewable resources, lignocellulosic materials are ideal candidates as alternative feedstock for bioethanol production. Cassava residues (CR) are byproducts of the cassava starch industry which can be mixed with lignocellulosic materials for ethanol production. The presence of lignin in lignocellulosic substrates can inhibit saccharification by reducing the cellulase activity. Simultaneous saccharification and fermentation (SSF) of furfural residues (FR) pretreated with green liquor and hydrogen peroxide (GL-H2O2) with CR saccharification liquid was investigated. The final ethanol concentration, yield, initial rate, number of live yeast cells, and the dead yeast ratio were compared to evaluate the effectiveness of combining delignificated lignocellulosic substrates and starchy substrates for ethanol production. Results Our results indicate that 42.0 % of FR lignin removal was achieved on FR using of 0.06 g H2O2/g-substrate and 9 mL GL/g-substrate at 80 °C. The highest overall ethanol yield was 93.6 % of the theoretical. When the ratio of 0.06 g/g-H2O2-GL-pretreated FR to CR was 5:1, the ethanol concentration was the same with that ratio of untreated FR to CR of 1:1. Using 0.06 g/g-H2O2-GL-pretreated FR with CR at a ratio of 2:1 resulted in 51.9 g/L ethanol concentration. Moreover, FR pretreated with GL-H2O2 decreased the concentration of byproducts in SSF compared with that obtained in the previous study. Conclusions The lignin in FR would inhibit enzyme activity and GL-H2O2 is an advantageous pretreatment method to treat FR and high intensity of FR pretreatment increased the final ethanol concentration. The efficiency of ethanol fermentation of was improved when delignification increased. GL-H2O2 is an advantageous pretreatment method to treat FR. As the pretreatment dosage of GL-H2O2 on FR increased, the proportion of lignocellulosic substrates was enhanced in the SSF of the substrate mixture of CR and FR as compared with untreated FR. Moreover, the final ethanol concentration was increased with a high ethanol yield and lower byproduct concentrations.