The Selective Synthesis Of Fructose To 5-hydroxymethyl-furfural(HMF) Catalyzed By Solid Acid

As we all know that fossil resource which is main building blocks for chemical productsis facing a danger of exhaustion and bringing to environment pollution. Today as people areconvinced of the sense of environment protection and green chemistry concept the fullyutilization of reproducible and redegradative resources which could produce importantindustrial matetrials by chemical synthesis is a good way to solve resource exhaustion andenvironment pollution. Biomass is payed more attention because it is abundant,renewable,lowcost and a lot of valuble drug intermediantes and polymeric materials can be preparated fromthem.In this thesis the dehydration of fructose to 5-hydroxymethyl furfural(HMF) catalyzed bysolid acids was studied. The main problem of this reaction was the low selectivity andequipments erosion and environment pollution can be bringed to by catalysts. So choosing acatalyst with high selectivity is the key of solving the problems. Heteropolytic acids are highactive catalysts and have already been used in chemical industry. In our experiments goodresults were found in the study of heteropolytic acids and its salts. By investigating somefactors such as reaction time,reaction temperature,solvent,additive,dosage of catalyst andfructose concentration following conclusions weregot: high temperature favor highselectivity; it is good for restraining byreactions that dehydration of fructose in DMSO andpoly(1-vinyl-2-pyrrolidinone)(PVP) was added;the salts of heteropolytic acids are capable ofhigher catalic activity than relevant heteropolytic acids;the best reaction condision: 30wt%fructose,MHPA1(1 mol%), DMSO, PVP(20 wt%),155℃, 5 min, yield 77.9%. Otherwiseproduct was treated in different ways and the loss can be decreased to the lowest level byvaccum distillation after acid was neutralized and isolated yield is 64%. Finally 2,5-fural-dicarbaldehyde and 2, 5-bis-(hydroxymethyl)furan were produced from HMF and thestructures were confirmed by 1H NMR and MS spectras.