Study On Selective Catalytic Hydrogenation Of Polycyclic Aromatic Hydrocarbons In Heavy Oil

Heavy oil contains a large number of polycyclic aromatic hydrocarbons?PAHs?,which are of high-pollution,carcinogenesis,induced genetic variation and low degradation.The selective catalytic hydrogenation of PAHs can not only eliminate the jeopardize caused by pahs,but also the catalytic hydrogenation products can be used as fuel,chemical and intermediate raw materials,it can effectively improve the utilization efficiency and economic value of heavy oil.Therefore,this study takes polycyclic aromatic hydrocarbons in heavy oil as the research object,and systematically studies different selective hydrogenation products according to different purposes of selective hydrogenation methods.In this study,saturated hydrogenation catalysts and bi-function catalysts were designed according to different purposes of selective hydrogenation methods,and the hydrogenation performance was studied and optimized in the end.Preliminary filtering and processing optimization of hydrostturation catalysts:physical characteriz of the catalysts were analyzed by means of XRD,XPS,SEM and BET.The catalyst was optimized by four factors:carrier,metal ratio,assist-metal ratio and assist-metal ratio.By investigating the reaction temperature,hydrogen pressure,reaction time and agent oil ratio four process conditions,combined with four components on the evaluation of the catalyst and the optimal catalyst hydrogenation saturation of 3%distillation range analysis helps the modified X-Al₂O₃ assist-metal Co load NiMo?6:9?catalysts and 380°C,8 MPa,60 min and agent oil ratio1:20 as the optimized technological parameters.Preliminary filtering and processing optimization of dual-effect composite catalyst:characterization of crystalline,surface speciation,apparent structure,acidity and pore properties of the catalyst;The effects of different molecular sieve types,compounding methods and compounding ratio on the performance of dual-effect composite catalyst were investigated.reaction temperature,hydrogen pressure,reaction time and agent oil ratio four process conditions filtering process,the best choose is using mechanical complex legal 4:6 A catalyst and hydrogenation saturation catalyst optimal and 400°C,10 MPa,60 min and agent oil ratio1:20 as the optimized process conditions.Finally,with raw materials oil hydrogenation and catalyst recycle catalyst for comprehensive performance evaluation for the design,through the evaluation experiment it is concluded that the oil in the raw material of two kinds of catalysts for many times after the catalytic hydrogenation of saturates content were 65.91%and 72.91%respectively and fraction is given priority to with 160³80°C is an obvious effect,after useing for the first time the catalyst activity losses seriously,when the two comparative analysis found that the hydrogenation saturation catalyst obtain more naphthene products,while more paraffin product was obtained by bi-function catalyst,the overall performance of the bi-function catalyst is better than that of hydrostturation catalyst.