苯、乙烯和乙苯在HZSM－5及其负载Co，Zn的催化剂上的吸附和脱附行为

STUDY ON THE ADSORPTION AND DESORPTION BEHAVIOR OF BENZENE, ETHYLENE AND ETHYLBENZENE OVER HZSM-5 AND HZSM-5-SUPPORTED Co AND Zn CATALYSTS

用ＴＰＤ（程序升温脱附）和ＴＰＳＲ（程序升温表面反应）技术研究了苯、乙烯和乙苯在ＨＺＳＭ－５及其负载Ｃｏ、Ｚｎ的催化剂上的吸附和脱附行为．结果表明，苯的ＴＰＤ峰皆为弥散的单峰．乙烯在ＨＺＳＭ－５及Ｚｎ／ＨＺＳＭ－５催化剂上发生二聚、歧化和芳构化反应，在Ｚｎ／ＨＺＳＭ－５上乙烯的二聚和歧化反应能力减弱，芳构化能力增强．苯和乙烯ＴＰＳＲ行为与吸附苯和乙烯的先后顺序有很大关系，主要产物是甲苯、乙苯和苯乙烯等．乙苯在各种催化剂上发生裂解和脱氢反应．结合活性评价结果，对苯和乙烯在催化剂上直接生成苯乙烯的途径进行了探讨．

he adsorption and desorption behavior of benzene, ethylene andethylbenzene over HZSM-5 and HZSM-5-supported Co and Zn catalystshave been studied with TPD and TPSR techniques. The TPD spectra ofbenzene over the catalysts are all broad single peak. The dimerization,disproportionation and aromatization of ethylene occur during the TPSRprocess, Zn modifying HZSM-5 catalyst reduces the dimerization anddisproportionation of ethylene, but increases the aromatization of ethylene.The TPSR behavior of benzene and ethylene is related to the adsorption sequence of benzene and ethylene, the main products aretoluene, ethylbenzene and styrene. Ethylbenzene adsorbed on catalystis cracked to benzene and toluene, and dehydrogenated to styrene.Theformation route of styrene from benzene and ethylene over the catalystshas been discussed.