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Since the 20th century, traditional fossil fuels are depleting intensified worldwide energy crisis, development of new and alternative energy sources to become major problems facing the world. Biomass including waste and residues in agricultural production, trees and grasses, abundant, is the world's most abundant reserves of renewable resources, with the potential to replace petroleum-based industries. Cellulose is the main component of raw material, which is composed of glucose units by beta-1, 4 glycosidic bond linked together, each of the glucose chains linked by hydrogen bonds formed between a supramolecular structure, this compact structure makes cellulose difficult to be degraded. This article from the reaction solvent system and catalyst separation system perspective on this important topic cellulose hydrolysis research. In this study chloride ionic liquid 1 - ethyl - 3 - methyl imidazole ([EMIM] Cl), chloride, 1 - butyl - 3 - methylimidazolium ([BMIM] Cl), chloride, 1 - allyl 3 - methylimidazolium ([AMIM] Cl) in the direct conversion of three systems Cellulose HMF, influences of different acid catalyst, the amount of chromium chloride, cellulose concentration and moisture content on the yield of HMF. hydrochloride as catalyst, HMF yield reached 50%, while tried to acidic ionic liquid ([BMIM] HSO 4 ) and ([BMIM] H 2 PO 4 ) as a solvent and catalyst catalyzes the hydrolysis of cellulose directly. HMF cellulose hydrolysis kinetics was studied and the establishment of a simple kinetic model, research shows that the overall reaction includes a one response and two consecutive zero-order reaction. Study is to use a large number of acid and enzymatic hydrolysis of cellulose, but the residual liquid from the reaction product and catalyst separation is energy. Based on this actual process of hydrolysis of biomass, we first designed and synthesized a magnetic solid acid catalyst to solve the problem of catalyst separation by TEM, X-ray diffraction analysis and specific surface area measurements show iron oxide nano-particles are well wrapped in silica, the catalyst performance of highly ordered mesoporous structure. The catalytic effect of the catalyst of the type of biomass materials include cellobiose, starch, cellulose hydrolysis shows better results. Cellobiose hydrolysis can be 96% of glucose, hydrolysis of amorphous cellulose, yield 50% glucose. To prove that the catalyst can be hydrolyzed lignocellulose, we choose untreated corncob as raw materials, to obtain 45% of the total reducing sugar yield. Importantly, by using this new catalyst and the catalyst separation we omitted the step of concentrating the reaction solution, the hydrolysis catalyst is recycled using a cubic effect is not significantly decreased.
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