摘要
以正硅酸乙酯为硅源,采用溶胶-凝胶法制备了负载磷钼杂多酸铵催化剂(S-AMPA),利用XRD、IR以及电位滴定等方法对催化剂进行了表征,并考察了催化剂用量、反应时间和温度等反应参数对催化剂的苯液相硝化反应催化性能的影响。结果表明,溶胶-凝胶法制备的S-AMPA具有典型的Keggin结构,而且负载后催化剂的酸度和酸性点总量都明显增大;反应时间等反应参数对苯催化硝化反应有明显的影响,在优化实验条件下,苯硝化转化率可达96%;反应后催化剂活性组分有所损失,但催化剂整体物相和结构没有发生明显变化。
Ammonium molybdophosphat（S-AMPA） catalyst supported on silica was synthesized by sol-gel method with ethyl silicate as silicon source.The properties were characterized by XRD,IR spectra and the potentiometric titration method.The influences of various parameters such as reaction time and temperature on liquid nitration of benzene have also been systematically studied.XRD and IR indicated that the Keggin structure was retained after AMPA catalyst supported on silica.And the results of potentiometric titration revealed that the maximum acid strength and the total number of acid sites of S-AMPA were more than these of unsupported catalyst.The catalyst exhibited high catalytic activity for nitration reaction and the highest yield is up to 96%.The phase and structure of catalyst have not obvious change after used,although the active component had some loss in the reaction progress.
出处
《化学试剂》
CAS
CSCD
北大核心
2011年第7期645-648,共4页
Chemical Reagents
基金
山东省教育厅科研基金资助项目(J09LB58)
聊城大学大学生科技文化创新基金资助项目(SRT10051X2)
关键词
磷钼酸铵
催化
苯
液相硝化
ammonium molybdophosphat
catalysis
benzene
liquid nitration
