CN-122010975-A - Method for preparing levoglucosone by catalyzing cellulose with sulfonated carbon and application thereof

CN122010975ACN 122010975 ACN122010975 ACN 122010975ACN-122010975-A

Abstract

The invention relates to a method for preparing levoglucosone by catalyzing cellulose with sulfonated carbon and application thereof, belonging to the technical field of biomass recycling and green catalysis. The method takes microcrystalline cellulose or waste cellulose biomass as a raw material, takes sulfonated carbon as a catalyst, and realizes the efficient preparation of the levoglucose ketone in an organic solvent system. The invention utilizes the synergistic effect of the acid active site provided by the sulfonated carbon and the organic solvent to promote the directional dehydration of cellulose to generate the levoglucosone, and effectively reduces the occurrence of side reactions such as hydrolysis, cracking, condensation and the like, thereby improving the selectivity and the yield of the levoglucosone and providing an efficient and green technical approach for the high-value conversion of cellulosic biomass.

Inventors

ZHANG SHICHENG
WU YILING
GAO JIE
DAI MINGFEI

Assignees

复旦大学

Dates

Publication Date: 20260512
Application Date: 20260316

Claims (7)

1. The method for preparing the levoglucosone by catalyzing cellulose with sulfonated carbon is characterized by comprising the following steps of: (1) Mixing cellulose, a sulfonated carbon catalyst and an organic solvent to obtain a reaction system, wherein the mass ratio of the cellulose to the sulfonated carbon catalyst is 1:1-1:10; (2) Placing the reaction system obtained in the step (1) in a closed reactor, and reacting at 150-300 ℃ for 1-120 min; (3) After the reaction is finished, cooling the reaction system obtained in the step (2), and carrying out solid-liquid separation to recover the sulfonated carbon catalyst to obtain a liquid phase product; (4) And (3) analyzing or separating the liquid-phase product obtained in the step (3) to obtain the levoglucosone.
2. The method for preparing the levoglucosone by using the sulfonated carbon catalyzed cellulose according to claim 1, wherein the organic solvent in the step (1) is a polar aprotic solvent, and the polar aprotic solvent is selected from one or more of tetrahydrofuran, 1, 4-dioxane, diethyl ether, isopropyl ether, tert-butyl methyl ether, acetonitrile, propionitrile, acetone, butanone, cyclohexanone, ethyl acetate, propyl acetate, butyl acetate, ethyl propionate, dimethyl carbonate, diethyl carbonate, N-dimethylformamide, N-dimethylacetamide, N-methylpyrrolidone, dimethyl sulfoxide, tetramethyl sulfoxide or sulfolane.
3. The method for preparing the levoglucosone by using the sulfonated carbon catalyzed cellulose according to claim 1, wherein the cellulose biomass in the step (1) comprises microcrystalline cellulose and waste cellulose biomass, and the waste cellulose biomass is selected from one or more of wheat straw, corn straw, rice straw, sorghum straw, cotton straw, soybean straw, corn cob, peanut shells, rice husks, coconut shells, sawdust, wood chips, wood shavings, branches, bagasse, waste paper, corrugated paper, cardboard, cotton fiber waste, waste cotton cloth, hemp fiber waste, bamboo powder, bamboo chips or wood powder.
4. The method for preparing the levoglucosenone by using the sulfonated carbon catalyzed cellulose according to claim 1, wherein the reaction temperature in the step (2) is 150-300 ℃ and the reaction time is 10-60 min.
5. The method for preparing the levoglucosone by catalyzing cellulose with sulfonated carbon according to claim 1, wherein the preparation step of the sulfonated carbon catalyst in the step (1) comprises the steps of mixing a carbon carrier and concentrated sulfuric acid in a reaction vessel, carrying out sulfonation reaction at 80-100 ℃, and then carrying out solid-liquid separation to obtain a solid product, namely the sulfonated carbon catalyst.
6. The method for preparing the levoglucosone by using the sulfonated carbon catalyzed cellulose according to claim 5, wherein the carbon carrier is one or more selected from the group consisting of activated carbon, mesoporous carbon, microporous carbon, ordered mesoporous carbon and carbon molecular sieves.
7. Use of the levoglucosone obtained by the preparation method of claim 1 in the catalytic conversion of practically waste biomass.

Description

Method for preparing levoglucosone by catalyzing cellulose with sulfonated carbon and application thereof Technical Field The invention belongs to the field of biomass resource high-valued comprehensive utilization, and particularly relates to a method for preparing levoglucose ketone by catalyzing cellulose with sulfonated carbon and application thereof. In particular to a method for preparing levoglucose ketone by catalyzing cellulose by sulfonated carbon in a heterogeneous system and application of the catalytic system in actual catalytic conversion of waste biomass. Background Cellulosic biomass is one of the most abundant renewable organic carbon resources in nature. As a biomass resource which is wide in source, renewable and low in price, the high-value utilization of cellulose and the waste biomass derived from cellulose has important significance in relieving the dependence of fossil resources, reducing the environmental load and promoting the green chemistry and sustainable development. In particular to efficiently converting the compound into a high added value platform compound, can provide an important raw material basis for green preparation of bio-based chemicals, fine chemicals and functional materials. The levoglucosone is an important biomass platform compound, contains unsaturated double bonds, carbonyl groups and chiral structural units in molecules, has higher chemical reaction activity and derivative conversion potential, can be used for preparing fine chemicals, medical intermediates, high-added value material monomers, green solvent precursors and the like, and therefore, is widely paid attention to. The directional preparation of levoglucosenone from cellulosic raw materials is considered to be one of the important ways to realize the high-value utilization of biomass. In the prior art, pyrolysis, homogeneous acid catalysis or a specific solvent system is adopted to promote dehydration reaction in the preparation of the levoglucosenone through cellulose conversion. Although the pyrolysis method can produce the levoglucosone, the method has the defects of high reaction temperature, more side reactions, complex product distribution, low target product selectivity and the like. Although the homogeneous acid catalysis method can promote the dehydration and conversion of cellulose to a certain extent, the method generally has the problems of equipment corrosion, difficult separation and recovery, complex post-treatment, large environmental burden and the like, and is not beneficial to continuous and industrialized application. Therefore, the development of a heterogeneous catalytic system which can achieve higher catalytic activity, better target product selectivity and easy separation and recovery of the catalyst has important significance. In recent years, the solid acid catalyst has the advantages of easy separation, recoverability, low corrosiveness, environmental protection and the like, and has good application prospect in the field of biomass catalytic conversion. The sulfonated carbon material has the characteristics of carbon material skeleton stability and sulfonic acid groups acidic sites, has the advantages of relatively simple preparation, adjustable acidity, good thermal stability, suitability for heterogeneous catalytic reaction and the like, and is considered as a biomass conversion catalytic material with potential. However, the research in the prior art for the directional preparation of levoglucosone by sulfonated carbon catalyzed cellulose is still relatively limited, and in particular, there is still room for further optimization in terms of achieving higher yields, higher selectivity and catalyst recycling in heterogeneous systems. In addition, the existing researches take model substrates such as microcrystalline cellulose and the like as research objects, and the researches on directly using the actual waste cellulosic biomass for preparing the levoglucosone are relatively few. Compared with a model substrate, the actual waste biomass is generally more complex in composition, contains hemicellulose, lignin, ash and other impurity components besides cellulose, and has obvious differences in mass transfer behavior, dehydration path and product distribution in the reaction process, so that the prior art is limited in the aspect of actual raw material applicability and application effect. Therefore, it is necessary to construct a corresponding catalytic conversion system on the actual waste biomass substrate to examine the application feasibility and technical effect of the catalytic conversion system in the high-valued utilization of the actual biomass resource. Therefore, a heterogeneous catalytic conversion method suitable for cellulose and actual waste cellulosic biomass is developed, so that the efficient preparation of the levoglucosone is realized, and the method has important research value and application prospect. Disclosure of Invention The invention aims t