摘要
通过程序升温脱附氨、红外、Hammett指示剂滴定法、正丁醇脱水、差热及热重手段研究引入不同含量的硅对载体的影响.结果显示:引入的硅和γ-Al2O3发生键合形成了新的Al-O-Si键;随着硅的含量增加,γ-Al2O3表面的总酸量及酸强度也增大.以苯加氢反应为探针,采用微催化脉冲色谱技术考察硅修饰的载体对催化活性的影响.结果表明:载体改性增加了对苯加氢反应的催化活性,降低了加氢反应的活化能;硅的影响以电子效应为主.
Silicon was introduced to modify the γ-Al_2O_3 carriers by impregnation methods. The effects of Si on the carriers were studied by means of NH_3-TPD, IR, Hammett indicator methods, dehydration of N-butanol, TG and DTA. The results indicated that the incorporated Si acted on the γ-Al_2O_3 to form new bond of Al-O-Si and that the total amounts of acid sites and the acid strength on the surface of γ-Al_2O_3 increased with the amount of introduced Si. Furthermore, Pt-and Pd-containing mono-metal supported catalysts were prepared by impregnation method with the γ-Al_2O_3 carrier modified by Si. The influences of Si on the catalytic activities were investigated by the micro-catalytic pulse chromatogram technology with the benzene hydrogenation as the probe. Experimental results revealed that the modification of carrier can increase the catalytic activity of benzene hydrogenation and decrease the activation energy of hydrogenation reaction. What's more, the results also showed that the influences of Si include the electronic effect and steric effect, whereas the electronic effect seemed to be principal.
出处
《华中师范大学学报（自然科学版）》
CAS
CSCD
北大核心
2004年第2期190-193,共4页
Journal of Central China Normal University：Natural Sciences
关键词
硅
Γ-AL2O3
改性
酸量
负载型催化剂
铂
钯
苯加氢
silicon
γ-Al_2O_3
modification
amounts of acid sites
supported catalyst
platinum
palladium
benzene hydrogenation
