Research Progress in Mechanism and Catalysts of Hydrodesulfurization for FCC Gasoline

The distribution of sulfur content in FCC gasoline,mechanism of hydrodesulfurization and catalysts for the HDS of FCC gasoline were reviewed and discussed.It is indicated that the sulfur compounds in FCC gasoline are mainly thiophenes and alkyl-substituted thiophenes which are the research focus for the mechanism of transformation on hydrotreating catalysts,and the distribution of sulfur is mainly in heavy fractions.The conventional HDS catalysts are not satisfied for HDS of FCC gasoline because alkene saturation is too high,but the HDS catalyst’s selectivity can be increased by changing acid–base properties of the catalyst.Current researches still focus on increasing the catalytic activity and selectivity,and formation of mercaptans by reaction between olefin and hydrogen sulfide in HDS process must be controlled seriously enough at the same time.