Energy & Fuels, Vol.22, No.6, 3955-3959, 2008
Cu-Ce Bimetal Ion-Exchanged Y Zeolites for Selective Adsorption of Thiophenic Sulfur
Adsorbents based on metal ion-exchanged Y zeolites (with single Cu and Cc or the combined Cu-Ce) were prepared. Then, the adsorptive desulfurization properties of the adsorbents were studied by a batch method at ambient conditions through model fuels, which were the iso-octane solution of sulfur compounds, and, in some cases, with a small quantity of toluene. The results show that CuCeY not only has the high sulfur adsorption capacity similar to (CuY)-Y-I but also has the high selectivity for sulfur compounds similar to (CeY)-Y-IV. Inductively coupled plasma-atomic emission spectrometer (ICP-AES) and X-ray photoelectron spectroscopy (XPS) studies indicate that Ce can not only use the surface of zeolite effectively and disperse at the geometric position, which is unfavorable to Cu, but also accelerate the conversion of Cu2+ to Cu+ and enhance the concentration of Cu+ on the surface of the adsorbent. Therefore, CuCeY exhibits an excellent sulfur adsorption performance. The saturated CuCeY can be regenerated with a solvent consisting of 30 wt % toluene and 70 wt % isooctane. In addition, about 90% of the sulfur adsorption capacity is recovered after regeneration.