Synthesis and hydrodesulfurization activity of unsupported Ni–Mo sulfide from nickel/cetyltrimethylammonium thiomolybdates

Ni-promoted cetyltrimethylammonium tetrathiomolybdate precursor was prepared by an aqueous solution precipitation method using (NH 4 ) 2 MoS 4 , [(C 16 H 33 )(CH 3 ) 3 ]NBr and NiCl 2 ·6H 2 O as raw materials. Unsupported carbon-containing Ni–Mo sulfides, Ni/C 16 –MoS 2 and Ni/C 16 –MoS 2,in , were obtained by ex situ thermal decomposition under N 2 atmosphere and in situ thermal decomposition of the precursor. EDS, BET, XRD, SEM and TEM techniques were employed to characterize these sulfide particles. Compared with Ni/C 1 –MoS 2 , the surface areas of Ni/C 16 –MoS 2 and Ni/C 16 –MoS 2,in were greatly improved and the carbon concentration of Ni/C 16 –MoS 2,in was adjusted to a lower level. Ni/C 16 –MoS 2,in showed higher hydrodesulfurization activity revealing that there was a synergistic effect between the structure of the active phase and the texture structure in the catalyst. Ni/C 16 –MoS 2 showed higher direct desulfurization selectivity while lower stacking number and shorter slab lengths of MoS 2 slabs explained this selectivity satisfactorily.