氮、磷、碳化物比较研究初探

γ-Al2O3supported molybdenum nitride, molybdenum phosphide and molybdenum carbide catalysts for hydrodesulphurization were prepared, respectively, by temperature-programmed reaction. The precursors were obtained by impregnation of γ-Al2O3 in an aqueous solution of ammonium heptamolybdate tetrahydrate [(NH4)6Mo7O24·4H2O] and diammonium hydrogen phosphate [(NH4)2HPO4], followed by drying at 120℃ and calcining at 500℃ in air. The three kinds of catalysts were characterized by XRD and BET. The results indicated that the molybdenum carbide prepared at a space velocity (CH4H2) of 10800h－1 has the biggest surface area of 175.7m2/g. The pore size distribution of molybdenum nitride catalyst was complex. The small pores of about 0.6225nm and the big pores of about 3.736nm were mainly observed in the supported molybdenum nitride catalyst. The active components in all of the three catalysts were dispersed on γ-Al2O3 uniformly. The conversion of dibenzothiophene on the three catalysts could respectively reach 85.5%、81% and 78.6%.