摘要
采用溶胶 凝胶方法,以P123为模板剂、正硅酸乙酯为硅源,合成出含有杂多酸铯盐的介孔分子筛CsxH3 xPW12O40 SBA 15。XRD表征结果表明,改性后的催化剂具有纯硅SBA 15分子筛晶体结构。将该催化剂用于合成丙烯酸正丁酯,并考察了不同Cs/P物质的量的比对反应活性的影响,其中Cs2.5H0.5PW12O40 SBA 15的催化活性最好。采用正交设计方法确定出各因素对反应结果的影响顺序为反应时间>反应温度>原料组成>催化剂用量,确定最佳操作条件为反应温度130℃,酸醇物质的量的比1∶1.2,反应时间5h,催化剂用量为总原料质量的5%(每克的物料催化剂用量为0.05g)。重复试验表明Cs2.5H0.5PW12O40 SBA 15具有良好的稳定性。
Cs_xH_(3-x)PW_(12)O_(40)-SBA-15 mesoporous molecular sieve was prepared by sol-gel method using P123 as templating agent and TEOS as silicon source. XRD patterns showed that the structure of Cs_xH_(3-X)PW_(12)O_(40)-SBA-15 remained perfect crystalline structure of SBA-15 molecular sieve. Influence of different Cs/P molar ratio on esterification over the catalysts was investigated, and (Cs_(2.5)H_(0.5)PW_(12)O_(40))/SBA-15 exhibited the best activity. Optimum reaction condition was obtained by orthogonal experiments as follows: 130 ℃,n(acrylic acid)∶n(butanol) =1∶1.2; reaction time 5 h,m(catalyst)∶m(reactants) =5%. Cs_xH_(3-x)PW_(12)O_(40)-SBA-15 showed good stability in repeated tests.
出处
《工业催化》
CAS
2004年第10期26-29,共4页
Industrial Catalysis
