Low-grade Diesel Mhug Catalyst Development And Industrial Applications

With the increase of processing imported high sulfur crude and deepening of residual oil conversion, the contents of S, N, gel and aromatics in the secondary processing diesel oil were increased, leading to bad oxidation safety performance. Meanwhile, the stricter and stricter environment protection regulations demand to produce environment-friendly oil products. The World Fuel Oil Regulation has stipulated the sulfur content in diesel oil II to be (?)300μg/g, cetane number to be (?)53, and aromatics content, <25% (m/m) . By the end of 2005, the specifications for motor diesel oil will tend to World Fuel Oil Regulation II. Therefore, in order to satisfy the requirements of stricter environmental regulations and processing high sulfur content crude, Research Institute of Qilu Branch Co., SINOPEC developed catalyst LH-03 for quality upgrading of poor diesel oil hydrogenation, with high desulfurization, denitrogenation and acromatics saturation activities.For the preparation of catalyst LH-03, large pore volume, large specific area aluminium hydroxide dry gel produced with carbonization method is selected as the raw material, then USY zeolite is combined in order to improve surface acidity of the catalyst. The catalyst is prepared with co-impregnation method, using W-Mo-Ni as active components, where W is from heteropoly wolframic acid to increase its hydrogenation activity and denitrogenation activity.Lab test, industrial scale-up as well as industrial sample charge and industrial commissioning appraisals were all made to the catalyst, and compared with two latest developed catalysts with good industrial results. It is indicated by the appraisal results that catalyst LH-03 has its hydrodesulfurization and denitrogenation activities and cetane number improving performance are superior to those of the two comparison catalysts. In June, 2001, catalyst LH-03 was successfully applied to the 1,200,000 t/a diesel oil hydrofining plant at medium pressure of Shengli Refinery.The calibration results show that catalyst LH-03 has the characteristics of good low temperature activity, high desulfurization, denitrogenation and degellation activities as well as low bed pressure drop.