Photothermocatalytic Wet Reforming of Waste Plastics to Syngas

The increasing accumulation of plastic waste in the environment poses a serious threat to the ecosystem and health sector, urging us to develop sustainable strategies to tackle this issue. Converting plastic waste into platform chemicals using sustainable energy and primary resources can mitigate environmental pollution and reduce CO₂ emissions. In this study, polyolefins were transformed into syngas through a wet reforming process over a nickel-supported oxygen vacancy-rich titanium dioxide (Ni/TiO_2-<i>x</i>) catalyst with water as the reactant under light irradiation. The focused light irradiation can readily increase the temperature in the reactor for the dehydrogenation and degradation of polyethylene (PE) to occur, followed by the wet reforming of PE-derived compounds and gaseous hydrocarbons to syngas. Additionally, the transfer of electrons from TiO_2-<i>x</i> to the nickel components under light irradiation facilitates the aforementioned reactions. The current work presents a sustainable strategy for valorization of plastic waste to syngas, serving as a platform feedstock for the subsequent production of various chemicals.