Study Of Residue Slurry-bed Hydrocracking With Oil-soluble Mo/Ni Catalysts

Karamay extra heavy atmospheric residue which has high viscosity,acid value,content of metal and nitrogen,is difficult to be processed with general process.While residue slurry-bed hydrocracking known for the adaptability of raw material,could be one way to process KAR.Furthermore,Oil-soluble Mo/Ni catalyst showed excellent hydrogenation activity.In order to solve the difficulties in the process of KAR,It is necessary to make a further research in KAR slurry-bed hydrocracking with oil-soluble Mo/Ni catalysts.Oil-soluble Mo,Ni,Mo/Ni catalysts after hydrogenation activity evaluation in the naphthalene hydrogenation,was applied in KAR slurry-bed hydrocracking.Then the effect of Mo/Ni catalyst concentration,the ratio of Mo/Ni,reaction temperature,reaction pressure,vulcanizing agents concentration,various additives on the products was studied.Reaction were carried out in an autoclave to investigate the change of structure and composition of C7-asphaltene researched by VPO,elemental analysis,1H-NMR,FT-IR,TEM,XRD and SEM et al.Moreover,the relevance between the yield,morphology of coke and C7-asphaltene properties was discussed.The results suggested that all oil soluble catalysts showed the activity in hydrogenation of naphthalene,and the activity of Mo was greater than Ni.Compared with Mo and Ni catalysts,Mo/Ni catalyst played a certain synergistic effect,especially when the quality ratio of Mo/Ni was between 7:3 and 2:3.Both the effect of hydrogenation and the cost of catalyst considered,the results was ideal when KAR slurry-bed hydrocracking was carried out at reaction temperature 435℃,initial reaction pressure 7 MPa,with 100μg·g^-1oil-soluble Mo/Ni catalyst and the ratio of Mo/Ni was 1:1.42.25% the yield of light oil,24.08% the yield of bottom oil and 1.62% the yield of coke could be obtained.The original sulfur in KAR could act as the sulfide additive,but the sulfide effect was not satisfying.300μg·g^-1 added vulcanizing agents could provide the catalyst good sulfide.SDBS tended to be one good additive for the reaction system,and the add of 150μg·g^-1 SDBS could decrease the yield of coke,especially coke formation on the surface of reactor.The content and condensation degree of asphaltene tended to increase with the extending of reaction time,while a few of large aromatic polymers started to convert into coke and the yield of coke increased slowly.Size and amount of particles on the surface of asphaltene increased,the number of aromatic layers became more and slice spacing became short before reaction 20 min.The content of asphaltene reached maximum at reaction 20 min,large amounts of asphaltene gathered together,the number of aromatic layers and slice spacing reached extremum.Plenty of large aromatic polymers generated coke fast after reaction 20 min,the yield and size of coke increased obviously,while the content and condensation degree of remaining asphaltene declined.Size and amount of particles on the surface of asphaltene decreased,the number of aromatic layers became less and slice spacing became long.