Deep desulfurization of model oil by photocatalytic air oxidation and adsorption using Ti(1−x)M x O2 (M=Zr, Ce)

Deep desulfurization of model oil by photocatalytic air oxidation and adsorption using Ti (1− x ) M x O 2 (M=Zr, Ce) was investigated. Ti (1− x ) M x O 2 (M=Zr, Ce) was prepared by urea gelation/co-precipitation method, and characterized by N 2 adsorption, XRD and UV-vis spectra. UV irradiation greatly enhanced the adsorptive capacity and selectivity of TiO 2 -ZrO 2 for organosulfur in model oil because organosulfur compounds were first photocatalytically oxidized to sulfoxides and sulfones over TiO 2 -ZrO 2 , which were then selectively adsorbed on the bifunctional material due to much higher polarities of generated sulfoxides and sulfones. The Ti/Zr molar ratio and calcination temperature were optimized to 5 : 5 and 500 °C with the sulfur removal of 99.6% after reaction for 2 h under UV irradiation. After adding 25 wt% toluene into model oil, the sulfur removal could still reach 97.2% after reaction for 7 h. TiO 2 -ZrO 2 could be well regenrated by washing with acetonitrile followed by thermal treatment in air.