Plasma boosted the conversion of waste plastics into liquid fuel by a peroxymonosulfate-hydrothermal process

• A novel strategy was conducted for plastic conversion under mild conditions. • Plasma boosted the conversion with a balance of radical effect and etching effect. • The boosting mechanism was revealed with experimental and computational analysis. Plastic wastes are growing fast over the world and impose great burden to eco-system. However, the plastics nurture abundant carbon resource and can be used as ideal raw materials to produce fuels. Hydrothermal process is considered as a promising strategy to convert plastics into fuel under a mild condition, but the conversion efficiency is often limited by the chemical inertness of plastics. Here, we propose a facile plasma treatment method to modify the plastic surface, aimed to boost the conversion of waste plastics into liquid fuel through a peroxymonosulfate (PMS) coupled hydrothermal process. We find that the sample after plasma treatment for 40 s displays 9.2 wt% weight loss with 8 h, which is 6 times that of the pristine sample. The plasma treatment can not only activate the inert surface but also enhanced the PMS activation process by establishing a balance between the radical effect and etching effect.