Study Of Hydrolysis Of Cellulose And Dehydration Of Fructose In Ionic Liquid

This thesis focuses on hydrolysis of cellulose and dehydration of fructose to5-hysdroxymethyl fufural (HMF) in ionic liquid, using acidic ionic liquid and Hβ as catalyst, respectively.(1)A series of acidic ionic liquids (methylimidazolium-based acidic ionic liquids and pyrrolidonium-based acidic ionic liquids) which were used as catalyst were synthesized and characterized. Ionic liquid1-butyl-3-methylimidazolium chloride salts ([BMIMJC1) was used as the solvent of cellulose, hydrolysis of cellulose into glucose in the presence of acidic ionic liquid was investigated systematically.(2)Cellobiose was used as the model compound to find the stable condition of cellobiose-glucose. And then, the influences of water content, procedure of adding water, catalyst dosage, reaction temperature and reaction time on the catalytic properties in the conversion of cellulose were studied. It was shown that pyrrolidonium-based acidic ionic liquids are better in the hydrolysis of cellulose into glucose compare to methylimidazolium-based acidic ionic liquids. The results indicated that under optimized reaction conditions, when temperature was110℃,n(Catalyst):n(Glucose unit in cellulose): n(H2O)=1:3:210, the yield of glucose were68%.(3)Hβ was modified by nitric acid, citric acid and phosphorus. And then, FT-IR was used to characterize the modified-Hβ.(4) The influences of ionic liquis’types, dosage of Hβ, reaction temperature and reaction time on the catalytic properties in the conversion of fructose were studied. Ionic liquid1-ethyl-3-methylimidazolium bromide salts ([EMIM]Br) was used as the solvent of fructose, the modified-Hβ were used as catalysts, dehydration of fructose into HMF was investigated systematically. The result indicated that [BMIM]Cl is better in the dehydration of fructose into HMF compare to [EMIM]Br. The FT-IR spectra of pyridine on modified-Hβ and the catalytic result of dehydration of fructose reflected that the Lewis acid center on the Hβ play a leading role in the conversion of fructose into HMF.