Coupling aquathermolysis of water-heavy oil-methanol catalyzed by o-phenanthroline-Cu(II) complex at low temperature

In this study, a Cu(II) coordinated complex was synthesized using o-phenanthroline and copper chloride. The synthesized complex, serving as a aquathermolysis catalyst, significantly reduces heavy oil viscosity at lower temperatures. Studies indicate that at a reaction temperature of 200 °C, with a catalyst concentration of 0.1% and a reaction duration of 6 h, heavy oil viscosity significantly reduces. Heavy oil viscosity dropped from 392,000 mPa∙s to 63,000 mPa∙s, achieving an 83.93% reduction rate. This catalyst maintains superior catalytic performance at lower temperatures compared to other catalyst types. Using methanol as a hydrogen donor further enhances the catalyst's effect, increasing the heavy oil viscosity reduction rate from 83.93% to 88.63%. Thermogravimetric, four-component, and elemental analyses reveal that aquathermolysis of heavy oil primarily occurs in its heavier components. Following the aquathermolysis reaction, there is an increase in light components and a decrease in impurity atoms in heavy oil, resulting in improved crude oil quality.