New Solid Acid Catalysts And Their Applications

In industrial scale chemistry, many reactions are catalyzed by "solid acids". As heterogeneous catalysts, solid acids do not dissolve in the reaction medium, such as silica, alumina, zeolites and various other metal oxides. They are often used in esterification, alkylation, acylation, isomerization. Polymeric materials have been widely studied in fundamental research for over years. Polymers are suitable for the supports as heterogeneous catalysts, because low weight, easy production, immobilization of the organic framework, hydrophilic-hydrophobic properties can be adjusted. Therefore, the polymers have attracted great interest in the last decade.In this thesis, we aim to obtain high selectivity and efficiency of catalysts. This objective is a chieved through organic/inorganic modification of polymer. The acid active center was loaded on the polymer with high selectivity, and high efficiency catalyst. Firstly, we use the strong active sites of trifluoromethanesulfonic acid, sulfuric acid and polyoxometalates; Secondly, using the ability of polymer adsorption property, the raw material enrichment of the surface of catalysts, which increase the efficiency of our catalyst was prepared. These catalysts were studied by SEM, FTIR、XPS、13C NMR、TG、and BET. We also study the performance of our catalysts on the esterification of free fat acids. The main research contents are as follows:1. We synthesized a kind of catalyst of divinyl benzene (PDVB)-ionic liquids-acid and performed esterification of fatty acid. The preparation method are in the following steps:firstly, imidazole was loaded on the polymer; secondly,1,3-propane sultone immobilized; finally, the PDVB-ionic liquid and phosphotungstic acid were mixed together, We synthesize PDVB-ionic liquid-acid catalyst, which is a new catalyst. The catalyst studied on esterification of lauric acid with methanol, and get a high flied of 97.2%.2. Preparation and application of a series of 3-aminomethyl pyridine resin-1,3-propane sultone-acid catalysts. The preparation process is as follows:first,3-aminomethyl pyridine immobilized on polychlorostyrene ball, and then, the 1,3-propane sultone was added. Finally, H3PW12O40, CF3SO3H, H2SO4, H4SiW12O40 were mixed with 3-aminomethyl pyridine resin-1,3-propane sultone. The catalysts combine with the adsorption characteristics of polychlorostyrene and the high activity of H3PW12O40, CF3SO3H, H2SO4, H4SiW1204o, which have the high efficiency property. The catalysts have the advantage of without any pretreatment before use, can be repeatedly used, no corrosion to the reaction vessel, the high efficiency activity. To investigate the catalytic activity of the catalysts, we studied on esterification of long chain fatty acids, and get a high flied of 96%, we also successful synthesis of cellulose acetate butyrate.Acid active centers are introduced into the polymers through the formation of polymer-ionic liquid-acid.. The catalysts were performed on the esterification of long chain fatty acids, and we get a high conversion of 96% under a mild conditions, and successful get cellulose acetate butyrate.