Study On Synthesis Of Acidic Inoic Liquilds And Their Catalytic Activity For Rice Draw Hydrolysis

In this paper,1-(3’-sulfonic acidic group) propyl-3-methyl-imidazolium salts ([BmimC3]SO3-) and1-(4’-bromo)-butyl-3-methyl imidazolium bromide([Bmim]Br) were synthesized firstly. And then five acidic ionic liquids, including [Bmim]HSO4,[BmimC3SO3]HSO4,[BmimC3SO3]H2PO4,[Bmim]H2PO4and [Bmim]FeCl3Br, were synthesized Finally, the catalytical effection on the hydrolysis of cellulose in the rice straw were investigated by calculating the yield of reducing suger. The experimental results are summarized as follows:1The synthesis of acidic ionic liquildsA new synthesis method of1-(3’-sulfonic acidic group) propyl-3-methyl imidazolium salts ([BmimCs]SO3-) was developed, which combined reaction at room temperature with solvent recycling. The total yields of subject product ([BmimC3]SO3-)was89.98%in four times recycling of mother solution by combining reaction at room temperature with one-filtration. But, The total yields of subject product ([BmimC3]SO3-) was95.57%in four times recycling of mother solution by combining reaction at room temperature with two-filtration. These methods for synthesis of [BmimCs]SO3-were energy-saving, environment-friend, high yield with good quality, which provides a new synthetic method of1-(3’-sulfonic acid group)-3-methyl-imidazolium salts.Then,1-(4’-bromo)-butyl-3-methyl-imidazolium bromide [Bmin]Br and five kinds of acidic ionic liquilds, including [Bmim]HS04,[BmimC3SO3]HSO4,[BmimC3SO3]H2PO4,[Bmim]H2PO4and [Bmim] FeCl3Br were synthesized.2Catalysis of [Bmim]H2PO4on hydrolysis of rice straw(1) With [Bmim] H2PO4as catalyst, the conditions of hydrolysis of rice straw by heat-reflux was optimized. The optimal experimental conditions were as follows:the reaction temperature was120℃, the ratio of rice straw to [Bmim] H2PO4was5:4(g/g), reaction time was9h and the ratio of rice straw to water was1:20(g/mL).Under these conditions, the yield of reducing sugar was23.37%.(2) The conditions of hydrolysis of rice straw, with [Bmim] H2PO4as catalyst combined with microwave-assisted heat, was also investigated. The optimal experimental conditions were as follows:the microwave power was240W, the ratio of rice straw to [Bmim] H2PO4was5:5(g/g), reaction time was140min, the ratio of rice straw to water was1:80(g/mL). Under these conditions, the yield of reducing sugar was26.80%.3Catalysis effection of [Bmim]FeCl3Br combined with microwave assisted heat on hydrolysis of rice strawCombined [Bmim]FeCl3Br as catalyst with microwave-assisted heat, the conditions of hydrolysis of rice straw was investigated in this work. The optimal experimental conditions were as follows:the ratio of rice straw to [Bmim] FeCl3Br was5:4(g/g), reaction time was130min, the ratio of rice straw to water was1:40(g/mL). Under these conditions, the yield of reducing sugar was28.06%.