The Preparation Of Ionic Liquid-1-butyl-3-methyl Imidazolium Tetrafluoroborate By Microwave-assisted One-step Method

The ionic liquid—1- butyl -3- methyl imidazolium tetrafluoroborate had advantages that less saturated vapour pressure, less volatile, hardly inflammable, good electrical conductivity. It can be stable exist under 300℃, and shows good application foreground in the fields of separation, electrochemistry and catalyses reaction process.The aim product (1- butyl -3- methyl imidazolium tetrafluoroborate) was prepared by chlorine butane, nitrogen methyl imidazolium and tetrafluoroborate ammonium. Discover microwave precision composing reactor (CEM company, US) was used in this experiment. The reaction time, the ratio of reactant, reaction power was investigated, the experimental results shown that the optimal reaction condition is reaction temperature 70℃, the ratio of reactant(chlorine butane: nitrogen methyl imidazolium: tetrafluoroborate ammonium ) is 1:1:1, the reaction time are 7 hours, the yield of the product is 60 % in conventional heating method, the optimal reaction condition is reaction temperature 70℃, the ratio of reactan(tchlorine butane: nitrogen methyl imidazolium: tetrafluoroborate ammonium ) is 1:1:1, the power is 140W, the reaction time is 40 minutes, and the yield of the product is 80 % in microwave heating method, respectively.By comparing the two ways above, we could find that the reaction time of microwave-assisted method was only 10% that of the conventional method while the yield of production was 30% higher. The efficiency was promoted remarkable.