The Hydrogenation Of Heavy Oil In The Presence Of Oil-soluble Mo-base Catalyst

With the diminishing of petroleum resources and the growing maturity of heavy oil extraction technology,crude oil production showed a heavy and inferior trend.Suspension bed hydrogenation technology can process high-metal,high-carbon,high-sulfur low-quality heavy oil raw materials,gradually become the hot spot of research,in which the key is high-performance hydrogenation catalyst continuous progress.On the basis of simplifying the synthesis method of oil-soluble mono metal molybdenum catalyst,a new method for preparing self-vulcanized oil-soluble nickel-molybdenum bimetallic catalyst was proposed for the first time,and the hydrogenation reaction conditions of vacuum residue were optimized.The feasibility of using oil-soluble catalyst for heavy oil hydrotreating and viscosity reducing was preliminarily explored.The precursor of oil-soluble molybdenum-based catalyst was prepared by the direct reaction of ammonium tetrathiomolybdate solution and organic auxiliary agent.The preparation process of the catalyst was simplified and the yield of the catalyst was improved.The process conditions were optimized.The results show that the solubility of the oil-soluble molybdenum-based catalyst in the catalytic diesel oil is more than 9%,and the catalyst precursor can be decomposed from sulfide to form nano-scale dispersed active metal MoS₂,the average sheet length of 1 to 3nm,the average number of layers of 2 to 4.When the reaction temperature is from 410?to430?,the initial pressure of hydrogen is more than 10MPa,the concentration of catalyst is from 500ppm to 2000ppm and the reaction time is 1³h,the conversion rate of vacuum residue is more than 50%,and the total coke formation rate is less than0.6%.The results show that the catalyst has excellent properties of residue hydrotreating.The hydrogenation and viscosity reduction of the oil-soluble Mo catalyst was explored by using Canadian tar sands and Venezuelan heavy oil.The reaction temperature is 410?,the initial pressure of hydrogen is 10MPa,catalyst concentration is 200¹000ppm,the reaction time is 1h,the viscosity of Venezuela heavy oil is reduced from 6108 mPa.s?70??to 165 mPa.s?50??,the viscosity of Canada tar sands is reduced from 41500 mPa.s?70??to 101 mPa.s?50??.The results show that the oil-soluble Mo catalyst has excellent hydrogenation and viscosity reduction.The oil-soluble nickel-base catalyst precursor was prepared by the reaction of nickel salt and organic additives.The NiMo bimetallic catalyst was prepared by mixing with the oil soluble molybdenum catalyst,and the effect of Ni/Mo ratio on the hydrocracking effect of residual oil suspension bed was investigated.The results show that the introduction of metal Ni reduces the amount of metal added,thereby reducing the production cost,and the best Ni/Mo ratio is 1:2.However,the promoter Ni has no obvious promotion effect on the Mo based catalyst.It is possible that the simple mechanical mixing can not achieve the micro interaction between the promoter Ni and the Mo sulfide.Therefore,the precursor of oil-soluble NiMo bimetallic catalyst was prepared by direct reaction of ammonium molybdate and ammonium sulphide with organic auxiliary.The catalyst precursor can be decomposed from sulfide to form nano-scale dispersed active metal MoS₂ and NiS.The reaction temperature is 410?,the initial pressure of hydrogen is 11MPa,catalyst concentration?with metal Mo content meter?is 500ppm,the reaction time is 1h,the conversion rate of vacuum residue is 54.3%,the total coke formation rate is 0.67%,showing excellent bimetallic synergy.