Catalytic Conversion Of Polysaccharides Over Sulfonated Amorphous Carbon In Ionic Liquid

With the rapid consumption of fossil resources and more and more serious environmental problems, the exploitation and utilization of renewable resources is attracting more and more attention all over the world. At present, much more progress has been had on converting monose (glucose, fructose) into versatile platform compound (such as HMF). Since effective conversion of monosaccharides have been achieved, it’s significantly important to convert polysaccharides into HMF via one-pot process, which may reduce industry cost. Cellulose and inulin are polysaccharides consisted of glucose and fructose, respectively, which are abundant in nature and can be used as material for biomass processing and refining.The hydrolysis of cellulose and the production of HMF from inulin over sulfonated amorphous carbon were studied in ionic liquids. The content as follows:(1) Sulfonated sucrose, glucose and nut shell activated carbon catalysts were prepared with Sulfuric acid and characterized by Fourier transform infrared spectroscopy (FT-IR), Scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS) and Elemental analysis. The results show that the sulfonic groups could be brought into the carbon catalysts, and the sulfonated nut shell activated had least groups per unit of mass.(2) The hydrolysis of cellulose in the present of sulfonated amorphous carbon was investigated in ionic liquid. The effects of water amount, catalyst activity, catalyst amount, recycle of catalyst, reaction temperature and time on the hydrolysis of cellulose were researched. When the sulfonated sucrose carbon was used, a56.5%yield of glucose and a79.3%yield of total product could be obtained after the reaction was catalyzed using SC-SO3H with mass ratio of2:1(cellulose:catalyst) at120℃for4h with150ul H2O added by four times within30min. After recycle catalyst washed by sulfuric acid, it could be reused for the next experimental run.(3) The production of5-hydroxylmethylfurfural (HMF) from inulin over SC-SO3H was studied in an ionic liquid,1-butyl-3-methylimidazolium chloride ([BMIM]Cl). The effects of reaction solvent, water content, reaction temperature, reaction time, and catalyst dosage on the yield of HMF were investigated. Experimental results indicated that under the conditions that reaction temperature was100℃, the reaction time was60min, R=5(R represents the molar ratio of added water to fructose units in inulin), and the mass ratio of catalyst to inulin was3, the yield of HMF reached up to50%.