In situ preparation of well-dispersed CuO nanocatalysts in heavy oil for catalytic aquathermolysis

Abstract

Abstract We developed an in situ synthesis strategy for preparing well-dispersed CuO nanoparticles as aquathermolysis catalyst for viscosity reduction in Shengli heavy oil (China). A Cu(OH)2-contained microemulsion was employed as a carrier to disperse the precursor Cu(OH)2 to the heavy oil phase. Under aquathermolysis condition (240 °C, 2.5 MPa of N2), the Cu(OH)2 precursors would first be converted in situ to well-crystallized and size-homogeneous CuO nanoparticles naturally, catalyzed by which the viscosity of Shengli heavy oil could be reduced as much as 94.6%; simultaneously, 22.4% of asphaltenes were converted to light components. The agglomeration of the in situ prepared monoclinic CuO nanoparticles could be negligible throughout the catalytic reaction. Based on the characterization results of 1H NMR, elemental analysis and GC–MS of oil samples before and after catalytic aquathermolysis, the mechanism for viscosity reduction of heavy oil in the catalytic system was investigated.

Keywords

• Cu(OH)2-contained microemulsion
• In situ preparation
• CuO nanocatalyst
• Catalytic viscosity reduction
• Heavy oil