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13C-NMR chemical shifts were measured for C-4 and C-6 in a collection of eight crystalline glucoses and glucosides. The influence of the hydroxymethyl conformation was greater at C-4 than at C-6, with mean chemical shifts for gauche–trans molecules displaced 3.1 ppm (C-4) and 2.5 ppm (C-6) relative to gauche–gauche molecules. This information was used to interpret 13C-NMR spectra of crystalline celluloses...
Current knowledge about the integration of cellulose synthesis into cellular carbon metabolism and the cool temperature sensitivity of cellulose synthesis is reviewed briefly. Roles for sucrose synthase (to channel UDP-glucose to the cellulose synthase) and sucrose phosphate synthase (to recycle the fructose released by sucrose synthase to more sucrose) in secondary wall cellulose synthesis are described...
Brewer’s spent grain components (cellulose, hemicellulose and lignin) were fractionated in a two-step chemical pretreatment process using dilute sulfuric acid and sodium hydroxide solutions. The cellulose pulp produced was hydrolyzed with a cellulolytic complex, Celluclast 1.5 L, at 45 °C to convert the cellulose into glucose. Several conditions were examined: agitation speed (100, 150 and 200 rpm),...
An ecological and viable approach for the in situ forming silver nanoparticles (AgNPs) on cotton fabrics has been used. Silver nanocoated fabric of brownish yellow color (AgNPs, plasmon color) was characterized by scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS) and Fourier transform infrared spectroscopy (FTIR). SEM images revealed that the surface of the modified cotton was...
As a key renewable chemical for plastics and fine chemicals, the preparation of 5-hydroxymethylfurfural (5-HMF) from biomass is an important research topic. Cellulose, although abundant in nature, is difficult to convert to 5-HMF in good yields due to its recalcitrant and heterogeneous nature. In this work, we show an efficient two-step process for converting microcrystalline cellulose into 5-HMF...
Wheat straw is an abundant residue of agriculture which is increasingly considered as a feedstock for the production of fuels, energy and chemicals. The concentrated acid hydrolysis of wheat straw has been investigated in this work. Hemicellulose and cellulose have been efficiently converted into monomers of pentoses and glucose in high yields by a one-pot decrystallization-hydrolysis procedure. This...
We studied the acid hydrolysis of cellulose in an aqueous medium with the aim of maximizing glucose yield and minimizing the formation of by-products. The influence of reaction parameters such as temperature, acid concentration, acid strength and type of cellulose precursor on glucose yield was investigated. We observed that moderate reaction temperature and low acid concentration resulted in the...
A green and effective approach for comprehensive hydrolyzation of cellulose has been described. Several carbon-based solid acids were successfully prepared using various biomass (glucose, microcrystalline cellulose, bamboo, and rice husk) and used to catalyze cellulose hydrolysis. The acid groups (–SO3H and –COOH) were successfully introduced onto the surface of the carbon-based solid acid catalysts...
A novel willow-based solid acid catalyst was successfully prepared through sulfonation of pencil refill. This solid acid catalyst bearing SO3H and COOH groups shows macroporous structure, which is more suitable for conversion of cellulose into glucose, resulting in 78.0 % conversion and 65.0 % glucose yield at 160 °C for 8 h reaction time. Its activity was comparable to other carbon sulfonated acid...
This work proposes a new methodology for sugarcane bagasse pretreatment with ethanol, allowing production of lignin and enzymatically digestible cellulose in a one-step fractionation process. After ethanol-based organosolv pretreatment, the enzymatic digestibility of pretreated sugarcane bagasse was greatly enhanced: based on 100 g raw material, 39.96 g glucose could be obtained during enzymatic hydrolysis,...
Nano-Cu2O particles were synthesized on cotton fabric using CuSO4 as a precursor and glucose as a reducing and capping agent in alkali. The morphology, crystal phase and chemical structure of the fabrics were characterized by scanning electron microscope, X-ray diffraction, Fourier transform infrared spectroscopy and energy-dispersive X-ray spectroscopy. The colorimetric values of the treated fabrics...
In this study, ultrasound-assisted alkaline pretreatment is developed to evaluate the morphological and structural changes that occur during pretreatment of cellulose, and its effect on glucose production via enzymatic hydrolysis. The pretreated samples were characterized using scanning electron microscopy, infrared spectroscopy, and X-ray diffraction to understand the change in surface morphology,...
Dairy manure, one of the most abundant agricultural wastes generated in livestock farming, was pretreated with KOH aqueous solution to relieve the constraint of lignin, thus facilitating cellulose hydrolysis. The generated black liquor waste was used to prepare porous carbon. Glucose yield of 261 g/kg was obtained from dairy manure pretreated in 0.73 wt% HCl aqueous solution, much higher than that...
Saccharification of cellulose is a promising method for production of biofuels. However, low bioconversion efficiency of cellulose to soluble sugars is a major challenge. In this study, a cellulolytic strain of Fusarium oxysporum was cultivated on pure cellulosic substrates (avicel, α-cellulose, carboxymethylcellulose and methylcellulose) and conversion efficiency into glucose was investigated. Production...
A carbonaceous solid acid catalyst bearing weakly acidic carboxylic and phenolic functional groups was facilely prepared by the pyrolysis of cow dung followed by KOH activation. The prepared carbonaceous material showed low activity for the catalytic hydrolysis of raw cellulose in water (3.6% glucose yield). However, after the cellulose was pretreated by mixing with the carbonaceous catalyst in a...
In this paper, a silicalite-1 modified HY zeolite (HY/silicalite-1) was prepared and applied as an efficient catalyst to promote the hydrolysis of microcrystalline cellulose to glucose in ionic liquid 1-ethyl-3-methylimidazolium chloride ([Emim]Cl). Scanning Electron Microscope reflects a core–shell morphology of HY/silicalite-1. When using HY/silicalite-1 as catalyst instead of non-modified HY, the...
5-Hydroxymethylfurfural (5-HMF) from lignocellulosics has attracted attention as a platform chemical in chemical industry. In 5-HMF production processes, undesired degradation of 5-HMF by acid catalysts generally occurs, by which the 5-HMF yield is decreased along with formation of various types of by-products. In this study, we employed an acidic ionic liquid, 1-methylimidazolium hydrogen sulfate...
The hydrolysis of cellulose into glucose is a critical step for the conversion of lignocellulosic biomass into fuels and chemical products. The combination of supercritical water hydrolysis in ultrafast reactors, with the subsequent hydrolysis of the cello-oligosaccharides on silver-exchanged mesoporous mordenite zeolite, offers the possibility of a clear enhancement in the conversion of cellulose...
Superamphiphobic surfaces generally need a specific combination of low surface energy and re-entrant surface structure. Herein, we have created a hexane suspension of trichloro(1H,1H,2H,2H-tridecafluoro-n-octyl) silane, tetraethyl orthosilicate, silicon dioxide and titanium dioxide nanoparticles and modify a series of filter papers by one-step immersion in 10 min. Superhydrophobic and quasi-superoleophobic...
For the first time, the heterogeneous calcined forms of chromium loaded USY, ZSM-5 and Beta zeolites were studied for the synthesis of HMF from glucose and cellulose in different solvents such as 1-butyl-3-methylimidazolium chloride (BMIMCl) and dimethyl sulfoxide (DMSO). Catalysts were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, inductive coupling plasma-mass spectrometry...
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