硅铝柱撑磷酸锆的合成及在大豆油甲酯环氧化反应中的催化性能

Synthesis of Mixed Alumina Silica Pillared Zirconium Phosphate and Its Catalytic Performance in Epoxidation of Soyate

基于模板剂导向组装的方法制备了硅铝柱撑磷酸锆.对材料结构进行了表征,分析了硅铝柱撑结构的形成机制.结果表明,材料中铝分别以四面体与八面体的形式嵌入在柱撑结构的内部和层板表面.通过大豆油甲酯的环氧化反应考察了所得硅铝柱撑磷酸锆的催化性能,其催化选择性可达91.7%.反应历程的分析结果表明良好的层板柱撑结构使大分子的反应物能与层间活性位充分接触.硅铝柱撑磷酸锆的酸位特点及催化反应的动力学分析表明,铝源的引入提高了柱撑材料的Lewis酸含量,改善了柱撑磷酸锆对大豆油甲酯环氧化的催化性能.

The mixed alumina-silica pillared zirconium phosphate material was synthesized by template- directing self-assembly method. The textural properties of the material was systematically characterized by X-ray diffraction （ XRD ）, Brunauer-Emmett-Teller （ BET ）, Field emission scanning electron microscope （ FESEM ） and 27 A1 Nuclear magnetic resonance （27 A1 NMR）. The formation mechanism of the mixed alumina- silica pillared zirconium phosphate was further studied. The results show that the aluminum source is presented as etrahedral aluminum grafted onto the gallery and the octahedral aluminum on the layer, repectively. In the evaluation of catalytic performance, the epoxidation reaction of soyate is used to study the mixed alumina-silica pillared material. It exhibits 91.7% epoxy selectivity. The analysis of the catalytic behavior indicate that the ordered interlayer structure given by the template-directing self-assembly method provokes an adequately contact between the relatively large reactants of methyl soyate and the active sites. With the FFIR spectra of adsorbed pyridine and the analysis of the reaction kinetics, it can be found that the excellent catalytic performance compared with the pure silica pillared zirconium phosphate material and other solid acids is due to the abundant Lewis sites arising from the introducing of the alumina source.