SILICA-CERIA AS SUPPORT FOR THE PREPARATION OF NIMO(P) HYDRODESULFURIZATION AND HYDRODENITROGENATION CATALYSTS

New macroporous silica-ceria support was synthesised and tested in the preparation of NiMo(P) sulfide catalysts differing in the way of Mo and phosphorus introduction. Activity of catalysts in parallel HDN of pyridine and HDS of thiophene was compared with activity of a commercial NiMoP/alumina catalyst. Catalysts prepared from silica-ceria have higher HDS and HDN activities, produce a significantly lower amount of intermediate piperidine and possess the HDN/HDS selectivity comparable with the alumina supported catalyst. These properties can be ascribed both to the specific properties of support and phosphorus. Deposition of MoO3 was accompanied by consumption of OH groups of silica-ceria support; it was found that phosphorus facilitates significantly this reaction. The higher consumption of OH groups was in relation with increased activity of NiMoP catalysts; we suppose this behaviour is connected with a higher dispersion of the Mo phase.