Appropriate active-site in [Mo3S(S2)6]2- or [Mo2(S2)6]2- clusters for catalysis of thiophene hydrodesulfurization

Through a facial immersion method, thiomolybdates [Mo3S(S-2)(6)](2)(-) and [Mo-2(S-2)(6)](2)(-) clusters have been successfully anchored on SBA-15, and the loaded catalyst was characterized by various methods. The terminal/bridging sulfur atoms on the sulfide cluster have a strong tendency to combine with H atom and then transferred to the S atom of thiophene for hydrodesulfurization. The catalytic activity and desulfurization selectivity of the supported catalysts Mo3S13/SBA-15 and Mo2S12/SBA-15 were investigated at different temperature and different time. Direct hydrogenation of thiophene occurs presumably with the participation of -SH groups, produced from the opening of S-S bridges by hydrogen. And the desulfurization of thiophene occurs presumably with the breaking of C-S bond and formation of C-OH bond for the product is butanol. Mo3S13/SBA-15 and Mo2S12/SBA-15 display excellent catalytic performance. The conversion rate of thiophene is about 97% for Mo3S13/SBA-15 and 94% for Mo2S12/SBA-15, while the desulfurization selectivity is about 97% (Mo2S12/SBA-15) and 82% (Mo3S13/SBA-15).