固载化杂多酸催化合成乙基叔丁基醚

采用溶胶-凝胶法制备出含杂多酸(HPA)的硅基催化剂,在气相反应条件下,将该催化剂用于叔丁醇和乙醇合成ETBE的醚化反应。重点考察了催化剂的组成、催化剂预处理温度、反应温度、原料摩尔比、空速等因素对醚化反应性能的影响,得到杂多酸质量分数为30%,在450℃下处理后的催化剂为最佳,最佳反应条件:温度为110℃,WHSV为2h-1,n(乙醇)/n(叔丁醇)为1.5∶1。在该条件下考察催化剂的稳定性,结果表明,在72h内活性未发生明显变化,采用烧焦法对催化剂进行再生,重复实验结果说明,采用简单的烧焦再生法,催化剂的活性得到很好的恢复。

Synthesis of ETBE Over Heteropoly Acid Immobilized SiO2 Catalyst

Heteropoly acid immobilized Silica(HPA/SiO_2) catalysts were synthesized by sol-gel method. The etherification of ethanol with tert-butanol under vapor phase over HPA/SiO_2 was investigated. The influence of composition of catalyst, pre-treatment temperature and reaction conditions such as reaction temperature, ratio of reactants, mass rate on the reaction performance were studied. The results show the catalyst containing 30% heteropoly acid and pre-treated under 450 ℃ for 4 h is the best one. The optimum reaction conditions are gained: reaction temperature is 110 ℃, space velocity is 2 h~(-1), mole ratio of ethanol to butanol is 1.5∶1. The activity of catalyst is stable for 72 h under the optimum reaction conditions. The catalyst can be regenerated by burning method. The reuse results reveales this catalyst could be reused many times.