摘要
研究了载钯的锆基催化剂上甲醇丁酮一步法合成甲基异丙基酮和二乙基酮的反应.由ZrOCl2.8H2O等制备的Pd-ZrO2/MnOx/ZnO催化剂对甲醇丁酮一步反应合成甲基异丙基酮和二乙基酮具有良好的催化性能.重点考察了催化剂组成对反应的影响,结果表明:钯负载量对催化剂活性和选择性影响较大;锆基载体中添加MnOx和ZnO作为助剂是必要的,可以显著提高催化剂催化活性和选择性;负载少量钾可以有效降低重组分的生成.结合反应机理分析,反应经脱氢-缩合-加氢三个步骤,催化剂中加氢脱氢活性中心和酸性活性中心的匹配程度决定了催化剂的活性和选择性,催化剂上氢溢流的能力对催化剂的活性和选择性有明显的影响.
MIPK and DEK were prepared through one-step synthesis from methyl ethyl ketone and methanol on the catalyst of Pd-ZrO2/MnOJZnO. Effects of catalyst composition and reaction conditions were studied.The results indicate that amount of Pd loading on the catalyst influences obviously the activity and selectivity. MnOx and ZnO, as promoters on ZrO2-based catalyst,are necessary for higher activity and selectivity; and the potassium promoter-K is necessary for lowering selectivity of some high-boiling impurities. According to the reaction mechanism, this reaction contained three steps which are: dehydrogenation-condensation-hydrogenation. And in this catalyst, the match degree between the catalytic centers of (de)hydrogenation and condensation decides the catalytic activity and selectivity of the catalyst; at the same time, the hydrogen spillover also has obvious influence on the activity and selectivity.
出处
《浙江工业大学学报》
CAS
2007年第2期194-197,共4页
Journal of Zhejiang University of Technology