Thioetherification between mercaptan and diolefin is an efficient process to remove mercaptans in FCC gasoline at mild condition,during which the selective hydrogenation of diolefin to monoolefin is also expected.Here,SiO2 supported transition metal (Ee,Co,Ni,Mo and W) phosphides were tested forthe thioetherification of isoprene and butanethiol on a fixed-bed reactor at 120℃ and 1.5 MPa H2,and their structure before and after reaction was characterized by means of XRD,HRTEM,N2 sorption,CO chemisorption,NH3-TPD,XPS and TG.It was found that,among different metal phosphides,MoP/SiO2 showed the best performance,and the optimal nominal MoP loading was 25％.Apart from the nature of metal,the density of metal and acid sites determined the catalyst performance.Metal site was mainly responsible for hydrogenation of isoprene,while acid site dominantly contributed to the thioetherification and the polymerization of olefins.Moreover,a balance between metallic and acidic functions is required to arrive at a desired performance.Excessive metal sites or acid sites led to the over-hydrogenation of isoprene or the severe polymerization of olefins,respectively.25％MoP/SiO2 was tested for 37 h time on stream,and butanethiol conversion maintained at 100％;although isoprene conversion remarkably decreased,the selectivity to isopentenes exceeded 80％ after reaction for 11 h.We suggest that the deactivation of MoP/SiO2 is mainly ascribed to the butanethiol poisoning and the carbonaceous deposit,especially the former.