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

Abstract

Abstract Ni-promoted cetyltrimethylammonium tetrathiomolybdate precursor was prepared by an aqueous solution precipitation method using (NH4)2MoS4, [(C16H33)(CH3)3]NBr and NiCl2·6H2O as raw materials. Unsupported carbon-containing Ni–Mo sulfides, Ni/C16–MoS2 and Ni/C16–MoS2,in, were obtained by ex situ thermal decomposition under N2 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/C1–MoS2, the surface areas of Ni/C16–MoS2 and Ni/C16–MoS2,in were greatly improved and the carbon concentration of Ni/C16–MoS2,in was adjusted to a lower level. Ni/C16–MoS2,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/C16–MoS2 showed higher direct desulfurization selectivity while lower stacking number and shorter slab lengths of MoS2 slabs explained this selectivity satisf...