Heavy oil has 10 times the reserves of regular oil,making it a valuable petroleum resource.Heavy oil,on the other hand,has a high viscosity and a significant amount of colloid and asphaltenes,making its extraction difficult.It not only has significant mining expenses,but it also has several ecological and pollution issues.As a result,the advancement of downhole heavy oil in-situ upgrading technology has become a hotspot for study.The use of transition metal catalysts in in-situ heavy oil upgrading is investigated in this research.Dielectric barrier discharge plasma was used to make two catalysts:Ni/γ-Al2O3and Ni-Cu/γ-Al2O3.Dielectric barrier discharge plasma is a low-temperature plasma with a high electron temperature(>1000 K)and a low gas temperature(300~500 K),which allows for efficient metal catalyst synthesis and efficiently prevents excessive sintering.The catalysts were employed to upgrade heavy oils,resulting in fast viscosity decrease at low temperatures.Furthermore,the mechanism of heavy oil catalytic upgrading was explored,and the link between the catalytic reaction process and the improvement of heavy oil viscosity reduction rate was explained,using heavy oil family components,product analysis,and catalyst characterization.The study sets the path for heavy oil upgrading to be optimized.The following are the key conclusions.1.Ni and Cu may be evenly distributed on the surface ofγ-Al2O3and appear as nanoparticles in the catalyst generated by dielectric barrier discharge,considerably increasing reaction sites and catalytic activity.2.When creating Ni catalyst by dielectric electric discharge,the addition of Cu may effectively lower the catalytic reaction temperature,resulting in a low-temperature catalytic reaction;at the same time,it can effectively strengthen the catalyst’s stability,making it difficult to deactivate;3.The heavy components(colloids,asphaltenes)are swiftly decreased after heavy oil upgrading,while the light components are successfully enhanced,resulting in viscosity reduction and upgrading at the same time.4.The catalytic upgrading of heavy oil is accomplished primarily by hydrogenation,partial oxidation,and hydrothermal reaction to produce high-efficiency removal of sulfur,nitrogen,and oxygen in the heavy oil components,resulting in heavy oil upgrading and viscosity reduction. |