Adsorption desulfurization and weak competitive behavior from 1-hexene over cesium-exchanged Y zeolites (CsY)

摘要

The systematic research about the adsorption desulfurization and competitive behavior from 1-hexene over cesium-exchanged Y zeolites has been investigated.The structural properties of the adsorbents were characterized by X-ray diffraction (XRD),N2 sorption (BET) and thermal analysis (TGA).The effects of calcination temperature,calcination atmosphere,and adsorption temperature were studied by the dynamic and static tests.The competitive adsorption mechanisms between thiophene and 1-hexene were studied by in-situ Fourier transform infrared spectroscopy (in-situ FTIR) and temperature-programmed desorption (TPD).CsY adsorbents exhibited high selectivity for thiophene even when a large amount of olefins exist.In-situ FTIR spectra of thiophene and 1-hexene adsorption indicated that both thiophene and 1-hexene were mainly adsorbed on CsY via π-complexation.The higher desorption activated energy and higher adsorption heat of thiophene than 1-hexene obtained by thiophene-TPD and hexene-TPD has revealed that thiophene is adsorbed more strongly in CsY adsorbents than 1-hexene.