银催化剂载体表面处理的效应研究

Effect of carrier surface treatment on silver catalyst

通过对不同反应阶段的银催化剂试样的微观结构进行深层次的表征,发现银及关键助剂在载体表面的迁移及分布是影响银催化剂性能的关键因素。提出了用氨水/H_(2)O_(2)对氧化铝载体进行表面处理、改性,来改变载体表面的粗糙度及特性的创新方案。微反评价与表征结果表明,改良后银催化剂上环氧乙烷的选择性得到了显著的提升,银催化剂的诱导期大幅缩短。

It is found that the migration and distribution of silver particles and major promoters loaded on the carrier surface are the key factors to the performance of silver catalyst via in-depth characterization of the microstructure of silver catalyst samples in different reaction stages. Therefore,a new solution is proposed to change the roughness and feature of the carrier surface by using ammonia/H_(2)O_(2) to treat and modify the surface of alumina carrier. The microreaction and characterization results show that the selectivity of silver catalyst to ethylene oxide is significantly improved,and the induction period of silver catalyst is greatly shortened.