11-钨锌杂多酸盐催化合成乙酸乙酯

合成了K8CdZnW11O39（H2O）]、K8NiZnW11O39（H2O）]和K8CuZnW11O39（H2O）]3种具有Keggin结构的钨锌混配型杂多酸盐催化剂,以无水乙醇和冰乙酸为原料,催化合成乙酸乙酯。探讨了酸醇物质的量的比,催化剂的用量,反应时间和反应温度对酯化率的影响及催化剂的重复使用情况。结果表明反应最佳条件为：酸醇摩尔比为2.0,催化剂用量为原料质量的1%,反应时间为6.0 h,反应温度80℃,催化剂在连续使用5次情况下活性无明显下降。

Synthesis of Ethyl Acetate by 11-Tungstozincic Heteropoly Acid Catalyst

Three kinds of tungstozincic heteropoly acid complexes with Keggin structure,such as K8CdZnW（11）O（39）（H2O）],K8NiZnW（11）O（39）（H2O）],K8CuZnW（11）O（39）（H2O）],were synthesized.Ethyl acetate was prepared from glacial acetic acid and anhydrous ethanol catalyzed by tungstozincic heteropoly acid complexes.The effects of molar ratio of anhydrous ethanol to glacial acetic acid,dosage of catalyst,reaction temperature and reaction time on the esterification ratio and reuse of catalyst were discussed.The results showed the optimal condition is that the Molar ratio of ethanol to acetic acid is 2∶1, the dosage of catalyst is 1% of the material gross,reaction time is 6.0 h at 80 ℃.Moreover,after continuous use for five times,the activity of the catalyst hardly descend.