SÍNTESIS Y CARACTERIZACIÓN DE CATALIZADORES NO SOPORTADOS DE SULFUROS DE Ni, Mo Y W PARA LA HDS DE DBT SYNTHESIS AND CHARACTERIZATION OF Ni, Mo, W SULFIDE UNSUPPORTED CATALYSTS FOR HDS OF DBT

In this work we reported the synthesis and characterization of Ni, Mo and W Sulfides unsupported catalysts for hydrodesulfurization (HDS) of dibenzothiophene (DBT). To synthesize this kind of catalysts we used two different methods: (a) reaction of ammonium thiomolybdotungstate ((NH4)4MoWS8) with an aqueous solution of NiCl2·6H2O and (b) impregnation of ammonium thiomolybdate (ATM) and Ni(NO3)2·6H2O on ammonium thiotungstate (ATT). Subsequently, the catalysts were obtained by thermal decomposition of precursors (ex-situ activation) under a reductive atmosphere of H2S/H2 (15% H2S) at 400°C. The precursor prepared by reaction was first treated hydrothermically in a stainless steel autoclave at 250 °C for 2 h. The catalysts were tested in the HDS of DBT and characterized by SEM, TEM, XRD and BET specific surface area measurements. The catalysts obtained present poorly crystalline structures and different values of specific surface area and catalytic activity in the HDS of DBT.