醋酸甲酯水解用杂多酸类催化剂的筛选

Screening of the heteropoly acid catalysts for hydrolysis of methyl acetate

针对醋酸甲酯水解悬浮催化蒸馏工艺的要求,对杂多酸盐类酸性材料用作醋酸甲酯水解反应的催化剂进行了探索。从催化反应性能以及结构稳定性等方面对杂多酸及其盐进行评价和表征。实验证明,不同杂多酸及其盐的催化性能与杂多阴离子和阳离子的种类、阳离子取代基数目等因素有关,其中NH4H2PW12O40催化性能最好,反应重复性能也比较好;杂多酸铵盐反应前后结构无明显变化,具有良好的结构稳定性;NH4H2PW12O40的酸强度和总酸量也较高。

Salts of heteropoly acids were synthesized and their catalytic properties for hydrolysis of methyl acetate and structure investigated. The experimental results showed that activity of the salts of heteropoly acids is in association with their structure and composition. Ammonium sail of the heteropoly acid （NH4H2PW12O40）, with the strongest acidity （pKa=- 11. 99, close to that of H3PW12O40） and the highest total acidity, exhibited higher activity than other materials such as resin, heteropoly acids and other salts of heteropoly acids. It also showed good structural stability.