Catalytic Conversion Of Biomass-derived Carbohydrates To Methyl Levulinate And γ-vaterolactone

With the development of human society, namely depleting fossil resources andgrowing environmental concerns, has triggered great interest in searching forrenewable sources of energy and chemicals. Among these renewable resources,abundant renewable biomasses are regarded as a promising alternative tonon-renewable natural resources for the sustainable production of biofuels andbiochemicals in the future. Recently, extensive research has been performedworldwide to identify and study chemical or biological transformations for convertingbiomass into fuels and raw chemicals. Among these explorations, one attractiveapproach is the preparation and conversion of levulinate esters and γ-valerolactone,owing to its importance as one of the12important target chemicals and theirderivatives that US-DOE selected in their biomass program.It is widely used in food,agriculture, drugs, cosmetics, spice industries, as well as its derivatives.In the second chapter, a series of sulfated MMT catalysts with tuneable surfaceacid strength and site density were synthesized through a simple impregnation method.Among these catalysts, the20-SO42-/MTT exhibits the best performance for theconversion of carbohydrates to methyl levulinate. Under the optimal conditions, theconversion of glucose and fructose was up to100%, and the ML yield obtained were48%and65%, respectively. The sulfate groups on the MMT can promote the amountof strong acidic sites and the intensity of acidity, which is beneficial to the reaction.Among these molecules, γ-valerolactone is considered as one of the mostappealing molecules which could be used as a fuel additive, solvent, and liquid fuel.Furthermore, γ-valerolactone is an ideal precursor for the production of alkanes andvaluable chemicals. In the three chapter，the second chapter the reaction product ofmethyl levulinate as raw materials, by catalytic transfer hydrogenation toγ-valerolactone. Choose the suitable catalyst, study the influence of various factors onexperimental results, figure out the best reaction conditions. The nickel exhibits thebest performance for the conversion of methyl levulinate to γ-valerolactone. Under the optimal conditions, the yield of γ-valerolactone was up to100%. At the same time,the preliminary study was made on the mechanism of the synthesis of γ-valerolactonefrom methyl levulinate.