Enhanced degradation of polyethylene terephthalate plastics by CdS/CeO2 heterojunction photocatalyst activated peroxymonosulfate

Waste plastics have posed enormous to the environment, but their recycling, especially polyethylene terephthalate plastics, was still a huge challenge. Here, CdS/CeO2 was used as the photocatalyst to promote the degradation of PET-12 plastics by activating peroxymonosulfate (PMS) synergistic photocatalytic system. The results showed that 10 % CdS/CeO2 had the best performance under the illumination condition, and the weight loss rate of PET-12 could reach 93.92 % after adding 3 mM PMS. The effects of important parameters (PMS dose and co-existing anions) on PET-12 degradation were systematically studied, and the excellent performance of the photocatalytic-activated PMS system was verified by comparison experiments. SO4 center dot- contributed the most to the degradation performance of PET-12 plastics, which was demonstrated by electron paramagnetic resonance (EPR) and free radical quenching experiments. Furthermore, the results of GC showed that the gas products including CO, and CH4. This indicated that the mineralized products could be further reduced to hydrocarbon fuel under the action of the photocatalyst. This job supplied a new idea for the photocatalytic treatment of waste microplastics in the water, which will help recycle waste plastics and recycle carbon resources.

Automated summary

In this study, CdS/CeO2 was used as a photocatalyst to promote the degradation of PET-12 plastics by activating peroxymonosulfate (PMS) synergistic photocatalytic system. The experiments showed that 10% CdS/CeO2 exhibited the best performance under illumination, achieving a weight loss rate of 93.92% for PET-12 with 3 mM PMS. The effects of important parameters and co-existing anions on PET-12 degradation were systematically studied, and the superior performance of the photocatalytic-activated PMS system was verified through comparison experiments. The gas products detected during the process indicated the potential for further reduction to hydrocarbon fuel.