Efficient degradation of polystyrene microplastic pollutants in soil by dielectric barrier discharge plasma

Jingyuan Sima; Jun Wang; Jiaxing Song; Xudong Du; Fangfang Lou; Youqi Zhu; Jiahui Lei; Qunxing Huang

doi:10.1016/j.jhazmat.2024.133754

Efficient degradation of polystyrene microplastic pollutants in soil by dielectric barrier discharge plasma

J Hazard Mater. 2024 Apr 15:468:133754. doi: 10.1016/j.jhazmat.2024.133754. Epub 2024 Feb 8.

Authors

Jingyuan Sima¹, Jun Wang², Jiaxing Song¹, Xudong Du¹, Fangfang Lou¹, Youqi Zhu¹, Jiahui Lei¹, Qunxing Huang³

Affiliations

¹ State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China.
² State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China; Jiaxing Research Institute, Zhejiang University, Jiaxing 314000, China.
³ State Key Laboratory of Clean Energy Utilization, Institute for Thermal Power Engineering, Zhejiang University, Hangzhou 310027, China. Electronic address: China.hqx@zju.edu.cn.

PMID: 38394892
DOI: 10.1016/j.jhazmat.2024.133754

Abstract

In this study, the atmospheric dielectric barrier discharge (DBD) plasma was proposed for the degradation of polystyrene microplastics (PS-MPs) for the first time, due to its ability to generate reactive oxygen species (ROS). The local temperature in plasma was found to play a crucial role, as it enhanced the degradation reaction induced by ROS when it exceeded the melting temperature of PS-MPs. Factors including applied voltage, air flow rate, and PS-MPs concentration were investigated, and the degradation products were analyzed. High plasma energy and adequate supply of ROS were pivotal in promoting degradation. At 20.1 kV, the degradation efficiency of PS-MPs reached 98.7% after 60 min treatment, with gases (mainly CO_x, accounting for 96.4%) as the main degradation products. At a concentration of 1 wt%, the PS-MPs exhibited a remarkable conversion rate of 90.6% to CO_x, showcasing the degradation performance and oxidation degree of this technology. Finally, the degradation mechanism of PS-MPs combined with the detection results of ROS was suggested. This work demonstrates that DBD plasma is a promising strategy for PS-MPs degradation, with high energy efficiency (8.80 mg/kJ) and degradation performance (98.7% within 1 h), providing direct evidence for the rapid and comprehensive treatment of MP pollutants.

Keywords: Dielectric barrier discharge; Microplastics degradation; Plasma oxidation; Reactive oxygen species.