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采用水热法合成纯硅介孔分子筛Si-MCM-41,并用浸渍法将磷钨酸(PWA)负载到介孔分子筛Si-MCM-41上,制得了磷钨酸负载量不同的催化剂x%PWA/MCM-41.利用XRD,FT-IR,Py-IR,BET,TEM对载体和催化剂进行分析.结果表明,负载后的PWA颗粒粒径明显减小,粒径约为10个纳米,PWA在载体表面实现了均匀分布,通过叔丁醇和乙醇在高压反应釜内生成乙基叔丁基醚的反应测试催化剂的催化性能.结果表明,负载型催化剂和纯PWA相比,前者使叔丁醇(TBA)的转化率、ETBE的选择性有很大提高,当磷钨酸负载量为30%时TBA的转化率最大.最优的催化剂制备及反应条件是:载体550℃煅烧脱模,PWA负载量为30%,催化剂煅烧温度为300℃,醚化反应温度为120℃,乙醇与叔丁醇的摩尔比为2∶1,催化剂的用量为1.4g.
Hydrothermal synthesis of pure silicon mesoporous molecular sieve Si-MCM-41, and by impregnation of the phosphotungstic acid (PWA) supported on the mesoporous molecular sieve Si-MCM-41, obtained a different loading of phosphotungstic acid catalyst x% PWA / MCM-41.The results showed that PWA particle size was significantly reduced with a particle size of about 10 nm and PWA The catalyst surface was uniformly distributed and the catalytic performance of the catalyst was tested by the reaction of tert-butanol with ethanol to produce ethyl tert-butyl ether in the autoclave.The results showed that the former catalyzed the reaction of tert-butanol (TBA), the selectivity of ETBE is greatly improved, the conversion rate of TBA is the highest when the loading of phosphotungstic acid is 30% .The optimal catalyst preparation and reaction conditions are as follows: the carrier is calcined and demolished at 550 ℃, PWA The loading was 30%, the catalyst calcination temperature was 300 ℃, the etherification temperature was 120 ℃, the molar ratio of ethanol to t-butyl alcohol was 2:1, and the amount of catalyst was 1.4g.