AgY分子筛与甲烷中有机硫化物相互作用研究

Study on Interaction between AgY Zeolite and Sulfides in Methane

为了探讨在吸附分离过程中吸附剂与吸附质之间的相互作用,采用溶液离子交换法制备AgY分子筛,研究了动态与静态条件下二甲基硫醚(DMS)和乙硫醇(EM)在AgY分子筛上的吸附作用,再利用X射线光电子能谱(XPS)和傅立叶变换红外光谱(FT-IR)方法对AgY分子筛与DMS和EM间的相互作用进行了研究。结果表明:DMS在AgY表面的吸附较弱,在减压条件下即可从AgY表面脱除,而EM则通过-S-Ag键产生较强的吸附作用。这种差异是由DMS与EM的分子中S元素电荷密度的不同引起的。

The interaction between adsorbent and adsorbates is an important factor in the process of adsorption separation. Ag~ zeolite was prepared by a simple ion - exchange method in aqueous solution. Dimethyl sulfide （DMS） and ethyl mercaptan （EM） were used as probes to evaluate the adsorption capacity of the AgY for the sulfides. The interaction between adsorbent and the sulfides was investigated by X - ray photoelectron spectrosco- py （XPS） and Fourier transform infrared spectroscopy （ FT - IR）. The results showed that the relatively weak interaction between DMS and AgY zeolite was detected, which leads to the removal of DMS from AgY zeolite in low vacuum conditions. However, a more strong interaction was observed when EM adsorbed on the AgY zeolite, and it may be the effect of the - S - Ag bond. The difference of the interaction can be explained by the different charge density of S atom in DMS and EM molecules.