填料型La_2O_3/Al_2O_3-Al催化剂的制备及其催化性能

Preparation of Filler-Type La_2O_3/Al_2O_3-Al Catalyst for Catalytic Distillation and Its Catalytic Activity

以n水硝酸镧[La(NO3)3·n H2O]为原料,阳极氧化铝(Al2O3-Al)为载体,采用水热合成法将活性组分负载在Al2O3-Al上,制备了填料型固体碱催化精馏元件La2O3/Al2O3-Al,以丙酮缩合制备二丙酮醇为探针反应,考察了制备条件对催化剂性能的影响。采用XRD、SEM对催化剂的性能进行了表征。结果表明,活性组分La2O3均匀分散在载体Al2O3-Al表面上。当La(NO3)3·n H2O与氨水(NH3·H2O)的摩尔比为1∶8,油浴温度为160℃,油浴时间10 h,N2保护下焙烧温度为550℃,焙烧时间为2 h时,催化剂的活性最高,此时丙酮转化率为4.1%,二丙酮醇选择性98%。

A type of filler La2O3/Al2O3-Al solid base catalyst for catalytic distillation was prepared via a hydrothermal synthesis route using lanthanum nitrate as the raw material and anodic aluminum oxide as the template.The catalytic activity of La2O3/Al2O3-Al was evaluated by self-condensation of acetone as a probe reaction.The catalysts were characterized by means of XRD and SEM.The results show that the optimum conditions were as follows：the molar ratio of La（NO3）3·n H2 O to NH3·H2O was 1 ∶8,the oil bath temperature was 160 ℃,the oil bath time was 10 h,the calcination temperature was 550 ℃and the calcination time was 2 h in an N2 flow.Under the above conditions,the conversion of acetone was 4.1% and the selectivity towards diacetone alcohol was 98%.