Behavior of MoS2 intercalation compounds in HDS catalysis

MoS2 intercalated with various proportions of Co(OH) or Cp2Co+ were used as catalyst precursors for the hydrodesulfurization of thiophene in a differential flow reactor. X-ray diffraction and EXAFS were used to characterize the structures of the pristine and used catalysts. It was shown that the intercalates are unstable under the reaction conditions and revert to 2H-MoS2 with extrusion of the intercalated material, which is then converted to Co9S8. The catalytic activity, normalized to the BET surface area, and the product distributions at steady state are essentially identical to conventionally prepared, Co-promoted MoS2. It is argued that the pseudo-intercalation theory does not model the active site. (C) 1998 Academic Press.