Catalytic Dehydration Of Sucrose Into HMF Over Beta Zeolite In [EMIM] Br

Because of excessive exploitation and utilization, fossil resource, as the most important energy feeding of mankind, is faced with the depletion crisis; moreover, in modern society, consciousness of environmental protection and the concept of green chemistry are increasingly emphasized by people. Consequently, finding a new kind of environmentally friendly energy has been a necessary measure to mitigate the above both problem. Biomass has successfully attracted attention of many researchers because of its renewability, adequacy and no pollution. Through chemical synthesis method, biomass can be used to produce plenty of important industry chemical intermediated that can substitute for fossil fuels.HMF is a sort of significant product of biomass conversion, which can not only be a substitution for aromatic compounds from oil processing, but be utilized to produce liquid fuels. Until now, utilizing acid to catalyze saccharide dehydration is the main way producing HMF. Generally, saccharide contain single sugar, disaccharide and polyoses. Sucrose, as a sort of disaccharide, is studied frequently, because it is lower economic cost than single sugar, and has no complicated dissolution process which cellulose must be undergone. Liquid acid is widely used to the biomass conversion reaction, such as sulphuric acid, hydrochloric acid and phosphoric acid. However, these liquid acids can erode reactors, most importantly bring severe environmental pollution problems. As a result, in order to conquer these problems, a new method synthesizing HMF was studied by the thesis, in mixed solvent system, sugars were catalyzed by solid acid into HMF.DMA as the solvent, [EMIM]Br as the addictive of system, utilizing solid acid to catalyze sucrose dehydration into HMF. Firstly, by comparing different solid molecular sieve catalysts,5A, MCM-41, TS-1, HM, HZSM-5 and H-Beta, H-Beta was selected the most suitable catalyst, and then investigating the amount of H-Beta and [EMIM]Br in the reaction system. Secondly, by ion-exchange method, Cr was immobilized in Beta, the amount of Cr/Beta catalyst and its reusability were investigated. At the premium condition, the yield of HMF was enhanced apparently. In addition, Beta was also modified by two kind of metal, through the study of reusability of Cr/Cu/Beta, the running-off problem of Cr could be reduced. When the reaction temperature is 130℃, time is 90 min and the amount of Cr/Beta is 0.09 g, the yield of HMF attained the max value 68.3%of the system.