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Ionic liquids as a new kind of environment-friendly solvent and an acid catalyst, according to the reaction mixture and catalytic processes its own characteristics of ionic liquids functionality, making it a catalytic material having a certain function in order to meet required for the reaction. This thesis, in the conventional heating and microwave heating mode, respectively, to prepare 17 kinds of functional imidazoles, pyridines, quaternary ammonium salts containing a sulfonic acid group (-PS) functional group-ionic liquid and Heteropolyoxometallate catalyst, caprylic acid benzyl ester, succinic acid, dioctyl phthalate, trioctyl citrate synthesis reaction as a model to investigate the relationship between the catalyst structure and the catalytic activity; select the optimum catalyst of the acid to alcohol ratio, amount of catalyst, reaction temperature, reaction time and microwave power esterification rate. The experimental results show that: the anion and cation acidity and solubility and stability of the functionalized ionic liquid has an impact. Probe reaction of benzyl alcohol and the bitterness benzyl ester of octanoic acid synthesis PSPy] HSO4 to optimize the catalyst, acid-alcohol ratio of 1:1.5 octanoic acid 20 mol%, the amount of catalyst, the reaction time of 2.5 h conventional heating. to 120 ℃, the esterification rate reached 95.3%. In addition, the catalyst can be reused 10 times, activity remained unchanged, the esterification rate is still 94.2%. The power of 375 W of microwave heating a reaction time 15 min, the esterification rate reached 94.9%. Description show a high stability and catalytic activity of the catalyst under heating in two. Butanedioic acid and n-octanol synthesized succinic acid dioctyl probe reaction PSPy] HSO4 to optimize the catalyst, the acid-alcohol ratio of 1:4, the amount of catalyst octanoic acid 3 wt%, in traditional heating under The reaction temperature of 150 ° C, the reaction time of 3 h, the esterification rate of 93.49%. The catalyst can be reused 3 times after the esterification rate is still 92.79%, a power of 400 W, the microwave heating is only 15 min, the esterification rate reached 95.74%. Repeated 6 times after the esterification rate was maintained at 93.58%. Probe reaction of citric acid and n-octanol Synthesis trioctyl citrate, functional Heteropolyoxometallate is a self-separation of the catalyst, [MIMPS 3PW12O40 to optimize the catalyst, in conventional heating under acid to alcohol ratio of 1:5.5 8 wt% citric acid, the amount of catalyst, reaction temperature of 130 ℃, reaction time 3.0 h, the esterification rate reached 93.9%. Power of 400 W, microwave heating for 20 min, the amount of catalyst to 6 wt% of the citric acid esterification rate of 93.48%. After 8 times of repeated use esterification rate is maintained at more than 90%, indicating that the catalyst has a higher reaction activity and stability.
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