Hydrodesulfurization of dibenzothiophene using novel unsupported FeMoS catalysts prepared by in-situ activation from Fe (III)-containing thiomolybdate salts

Unsupported, carbon-containing molybdenum sulfide (MoS2) and bimetallic iron-molybdenum sulfide (FeMoS) catalysts are obtained by in-situ decomposition of (a) ammonium thiomolybdate (ATM), (b) Fe(III)-containing ATM, (c) hexyltrimethylammonium thiomolybdate (HTMATM), and (d) Fe(III)-containing HTMATM, labeled Mo-1, Mo-2, Mo-3 and Mo-4 catalysts. Their activity and selectivity are tested in the hydrodesulfurization (HDS) of dibenzothiophene (DBT). HDS activity of the novel bimetallic Mo-4 catalyst is nearly two times greater than that of the reference Mo-1 catalyst, with a less favorable selectivity towards hydrogenation products compared to the reference. Surface iron and carbon contents of the catalysts are found to affect their activity as follows; Mo-4 > Mo-3 ≈ Mo-1 > Mo-2.