Upgrading Of Vacuum Residue By Hydrogenation Over Ni-Mo Catalyst

Currently, the unstable world oil market, gradual boosting price of crude oil and increasing domestic demand of oil increases make it urgent to upgrade the petroleum processing technologies. And the increasing concerns on the environmental issue require the upgrading of petrochemical products. In addition, the growing demand of transportation fuel and decreasing consumption of heavy fuel oil make it very necessary to improve heavy oil hydro-upgrading technical. Hydrogenation technology of residual oil plays an important role in relieving China's energy shortage and raising oil processing level.In this paper, Ni-Mo bi-metal catalyst supported on Al2O3 was in-situ prepared to catalyze residue oil hydro-upgrading. The XRD analysis showed that main active metal components were in the form of MoS2, NiS, which are high dispersive supported on the support surface. Thus it is no need of presulfurization before the reaction of hydrogenation, which is different from conventional hydrogenation catalyst. The XRF analysis showed that the content of MoO3 and NiO is 29.6%and 7.6%, respectively.The raw material used in the experiments is the vacuum residue from Fushun Petrochemical. The effects of reaction conditions and catalyst amount on hydrogenation performances were studied. The results showed that residue hydro-upgrading is a synergy effect between thermal cracking and catalytic hydrocracking, wherein the effect of thermal cracking reaction on residue conversion is more obvious. In a non-hydrogen conditions, catalyst can promote the cracking of the residue. More coke will be formed owing to the absence of active hydrogen. In hydrogen atmosphere, the formation of coke was obviously suppressed, and the coke yield was greatly decreased. At 420 ? and hydrogen pressure of 7 MPa, the yield of light oil on the catalyst was 47.5% and the coke is less than 4%, which suggest that the quality of the resultant oil was obviously improved.The reaction temperature remarkably influences the conversion of residue, products distribution and coke yield. High reaction temperature results in the increase of the conversion of residue, gasoline and diesel yields. The conversion was enhanced from 59.3% at 390 ? to 87.3% at 430 ?, while the coke yield decrease. But further increasing the temperature, the coke yield quick increased to about 10% at 450 ?. It is thought that the cracking rate of residue exceeds the hydrogenation rate at high temperature, which leads to the polymerization of large free radicals from the cracking of the residue. Long reaction time and more catalyst are preferable to the conversion of residue and the enhancement of the coke. However, when the hydrogen pressure increases, the residue conversion and the yield of gasoline and diesel first increase and then decrease, while the coke yield reduces. Considering the residue conversion, light oil yield and coke yield together, the optimal operating conditions of Fushun Petrochemical vacuum residue hydro-processing reaction was as following:the reaction temperature 420 ?, initial hydrogen pressure 5 MPa, the amount of catalyst was 10%, reaction time was 1 h.84.8% residue conversion, the gasoline yield of 28.3%, the diesel yield of 25.5% along with the coke yield of 3.7%.