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Converting cellulose (Cel) into ethyl levulinate (EL) is one of the promising strategies for supplying liquid fuels. In this paper, the prepared sulfonated P-W-modified N-containing carbon-based solid acid catalyst (PWNCS), in which the Polyaniline (PANI) was employed as N and C precursors, successfully converted Cel into EL under the water-ethanol medium. The characterization results demonstrated that a tiny addition of P increased the Brønsted acid sites (BAS) content and defective WO 3 provided the Lewis acid sites (LAS), meanwhile, the sulfonation process did not change the fundamental structure but introduced the sulfonic groups to dramatically increase the acidic content. Therefore, under optimized reaction conditions, PWNCS realized about 100% Cel conversion and 71.61% of EL yield, furthermore, the selectivity of EL reached 89.14%. In addition, the effect of water on the reaction pathway of Cel to EL over PWNCS was proposed. The addition of water generally resulted in the hydration of defective WO 3 to reduce the LAS and increase BAS, which significantly inhibited the side reactions of retro-aldol condensation (RAC) and subsequent etherification reactions during Cel conversion and then improved the selectivity of EL., 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 B.V.)

The bi-functional Ni–W@C catalysts were prepared by one-pot reduction–carbonization method and used in hydrogenolysis of cellulose as well as raw lignocellulosic biomass to chemicals. The catalytic performance for cellulose conversion showed that it was more favorable for ethylene glycol (EG) production, obtaining the highest EG yield 60.1% over the Ni–W@C700 catalyst. The Ni–W@C bimetallic catalysts are systematically characterized with BET, XRD, Raman, XPS, TEM techniques and experiments to probe the active catalytic sites of the catalysts. The effects of calcination temperature of Ni–W catalysts, reaction time, temperature and H2 pressure on cellulose hydrogenolysis were investigated in detail. The Ni particles could lead to produce more W5+ active sites, which promotes the glucose retro-aldol condensation to break the target C–C bonds. Metallic Ni catalyzed C=O hydrogenation and C–C hydrogenolysis, which could also avoid the coke formation. The EG selectivity was dependent on the synergy of WOx and Ni metal sites. In addition, this synergistic effect between the metal and WOx could promote lignin component degradation in direct conversion of untreated raw lignocellulosic biomass, obtaining the propyl monophenolics including guaiacylpropane, syringylpropane and p-n-propylphenol with a total yield of 17.3 wt% besides EG. [ABSTRACT FROM AUTHOR]

Ethanol is an important bulk chemical with diverse applications. Biomass‐derived ethanol is traditionally produced by fermentation. Direct cellulose conversion to ethanol by chemocatalysis is particularly promising but remains a great challenge. Herein, a one‐pot hydrogenolysis of cellulose into ethanol was developed by using graphene‐layers‐encapsulated nickel (Ni@C) catalysts with the aid of H3PO4 in water. The cellulose was hydrolyzed into glucose, which was activated by forming cyclic di‐ester bonds between the OH groups of H3PO4 and glucose, promoting ethanol formation under the synergistic hydrogenation of Ni@C. A 69.1 % yield of ethanol (carbon mole basis) was obtained, which is comparable to the theoretical value achieved by glucose fermentation. An ethanol concentration of up to 8.9 wt % was obtained at an increased cellulose concentration. This work demonstrates a chemocatalytic approach for the high‐yield production of ethanol from renewable cellulosic biomass at high concentration. [ABSTRACT FROM AUTHOR]

Sn-β zeolite and PTSA-POM, made from the copolymerization of p-toluenesulfonic acid (PTSA) and paraformaldehyde (POM), were used for the production of 5-(hydroxymethyl)furfural (HMF) from glucose in an environmentally friendly solvent system including γ-valerolactone (GVL) and H2O. The effects of reaction temperature, reaction time, solvent, and catalyst-to-reactant ratio on the production of HMF were investigated. The combination of the Brønsted acid and Lewis acid catalysts largely improved the catalytic system and resulted in the production of HMF in 60.1 % yield at 140 °C in 30 min. The presence of water in the solvent had a positive influence on the production of HMF from glucose. The combination of the two catalysts also improved the catalytic performance for the production of HMF from cellulose and corn stalk. [ABSTRACT FROM AUTHOR]

Upon adding biomass under the action of water, heat, and catalyst, a wonderful chemical reaction occurs to obtain the ethanol. With the aid of Ni@C catalyst and H SB 3 sb PO SB 4 sb , cellulose is directly converted into ethanol with a high yield of 69.1 %, and an ethanol concentration up to 89 g L SP -1 sp . [Extracted from the article]

Molten salt hydrates (MSHs) are remarkable in breaking through the recalcitrant structure of microcrystalline cellulose and raw biomass. After being pretreated in 60 wt% LiBr at 130 °C for 2 h, cellulose crystallinity as well as degree of polymerization (DP) decreased. It was found that 91.3% yield of pretreated cellulose was removed from MSHs by filteration followed by being hydrolyzed into glucose with a high yield of 75.3% by dilute acid under mild reaction conditions. The pretreatment process also works on raw corn stover hydrolysis. After being pretreated at 100 °C for 5 h, 88.4% yield of cellulose in biomass was recovered and can be hydrolyzed into 54.9% yield of glucose with dilute acid. It was found that the cellulose in corn stover can be easier degraded compared with microcrystalline cellulose during MSHs pretreatment, which dues to the formation of acetic acid from hemicellulose hydrolysis. The proposed pretreatment technique presents a promising potential for glucose production from biomass in a commercial way. Unlabelled Image • MSHs pretreatment effectively decreased cellulose crystallinity and DP. • After being pretreated at 130°C for 2 h, 91.3% of cellulose was removed from MSHs via filtration. • Enhanced glucose yield of 75.3% was obtained from pretreated cellulose hydrolysis at mild condition. • 88.4% cellulose recovery and 54.9% glucose yield were obtained from MSHs pretreatment and hydrolysis, respectively. [ABSTRACT FROM AUTHOR]