Effect of CeO₂ morphology and Ru impregnation method on CH₄ selectivity reduction in polyethylene waste conversion to liquid fuels and lubricants

Hydrogenolysis of polyolefins offers a sustainable pathway by giving plastic waste a second life as valuable resources, transforming it into fuels and lubricants. Supported Ru catalysts have shown potential for depolymerizing polyolefins under mild conditions; however, depolymerization via terminal C-C bond cleavage can lead to the excessive formation of CH₄. This study investigated the effects of CeO₂ morphology and Ru impregnation method on the suppression of CH₄ formation and increasing liquid and wax proportions (C₅-C₄₁) in the production of liquid fuels and lubricants through polyethylene hydrogenolysis. Controlling the morphology of CeO₂ and impregnating Ru via electrostatic adsorption can enhance the formation of oxygen vacancies and strengthen the interaction between Ru and CeO₂. The presence of defects in CeO₂ also correlated with smaller particle size of Ru and a higher hydrogen reservoir site, which effectively suppress CH₄ formation.