摘要
应用有效的红外光谱技术研究了1-己烯在HY沸石上的吸附和结炭过程。1-己烯室温吸附后,引起小笼羟基伸缩振动谱带增强;在3140cm^(-1)附近出现了大峰包;并且硅终端羟基和小笼羟基伸缩振动谱带向低频发生位移。这些现象可能是吸附质促使部分超笼羟基转向小笼或质子迁移、以及1-己烯的π电子云与各类羟基作用的结果。升温脱气后,上述现象迅速减弱。当温度高于100℃时,可观察到1-己烯的进一步表面反应,有低环芳烃和多环类表面产物形成。温度越高,表面生成的焦炭结构越趋于复杂化。反应过程中,吸附态烃和气相烃结构不断变化,观察到了支链烃和多环芳烃结构物质。
The adsorption and coke formation of 1-hexene on HY have been studied by means of the effective spectroscopic technique. After 1-hexene adsorption at room temperature, the intensity of the cubooctahedra OH stretching band increases, a broad band around 3140 cm^(-1) appears, and the frequencies of the silicon terminal OH and the cubooctahedra OH shift to lower wave-numbers. These phenomena are probably due to the change of part of the supercage OH vibration direction toward cabooctahedra or proton caused by the adsorbent, as well as due to the interaction between π electrons of 1-hexene and various acidic OH groups in supercages; at the same time, the π electrons of 1-hexene force the OH stretching band shifting to lower wavenumbers. With temperature rising and degassing, the above mentioned phenomena diminish gradually. When the temperature is above 100℃, monocyclic aromatic species and polycyclic surface products are formed,which continue to react with the gaseous 1-hexene, and finally form coke as characterized by the 'coke' band around 1585 cm^(-1). Coke formed during 1-hexene reaction on HY is polycyclic aromatic in structure, to which many branched species with tertiary carbon atoms are linked. The higher the temperature, the more complex the structure of the coke formed.
出处
《石油学报（石油加工）》
EI
CAS
CSCD
北大核心
1992年第1期53-58,共6页
Acta Petrolei Sinica(Petroleum Processing Section)
基金
国家自然科学基金
