Preparation and ultra-deep hydrorefining performance of Ni-P/Al_2O_3-ZrO_2 Catalysts

摘要

A series of Al_2O_3-ZrO_2 (AZ-X) composite oxides with different ZrO_2 contents were prepared by a chemical precipitation method. Ni-P/AZ-X catalysts were prepared by temperature-programmed reduction. The supports and catalysts were extensively characterized by X-ray diffraction (XRD) and BET. The effects of support composition and P/Ni molar ratios on the catalytic performance of the catalysts were investigated by thiophene hydrodesulfurization (HDS) and pyridine hydrodenitrogenation (HDN). In comparison with Al_2O_3, Al_2O_3-ZrO_2 (20 wt% ZrO_2) composite oxide supported Ni-P catalyst exhibited higher activity and the activities of HDS and HDN increased by 7.5 % and 11.1%, respectively. Studies of Ni-P/AZ-X catalysts with varying initial P/Ni molar ratios indicated that oxidic precursors with molar ratios of P/Ni = 2/1 yielded catalyst containing phase-pure Ni_2P which exhibited optimal activity.