Lab-scale transport and activation of peroxydisulfate for phenanthrene degradation in soil: A comprehensive assessment of the remediation process, soil environment and microbial diversity

Xiupeng Yue; Yaping Zhang; Yongping Shan; Kai Shen; Wentao Jiao

doi:10.1016/j.scitotenv.2023.165771

Lab-scale transport and activation of peroxydisulfate for phenanthrene degradation in soil: A comprehensive assessment of the remediation process, soil environment and microbial diversity

Sci Total Environ. 2023 Nov 25:901:165771. doi: 10.1016/j.scitotenv.2023.165771. Epub 2023 Jul 31.

Authors

Xiupeng Yue¹, Yaping Zhang², Yongping Shan³, Kai Shen¹, Wentao Jiao³

Affiliations

¹ Key Laboratory of Energy Thermal Conversion and Control, Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, China.
² Key Laboratory of Energy Thermal Conversion and Control, Ministry of Education, School of Energy and Environment, Southeast University, Nanjing 210096, China. Electronic address: amflora@seu.edu.cn.
³ Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.

PMID: 37532036
DOI: 10.1016/j.scitotenv.2023.165771

Abstract

Electrokinetic transport followed by electrical resistance heating activation of peroxydisulfate is a novel in situ soil remediation method. However, the strategy of electrokinetic transport coupled with electrical resistance heating and the comprehensive evaluation of restored soil need to be further explored. In this study, a lab-scale simulation device for in situ electrokinetic transport coupled with electrical resistance heating activation of peroxydisulfate was constructed to monitor the transport and transfer of peroxydisulfate, target pollutants, and process parameters, and the physicochemical properties and bacterial community of treated soil were evaluated. The results showed that adding 10 wt% peroxydisulfate to both the anode and cathode resulted in the optimized transfer rate and cumulative concentration of peroxydisulfate under electrokinetics. After 8 h, the cumulative concentration of peroxydisulfate reached 66.15- 166.29 mmol L^-1, which was attributed to the migration of a large amount of S₂O₈^2- from the cathode to the soil under electromigration. Additionally, the anodic interfacial electric potential was improved, which was more conducive to electroosmotic transport of peroxydisulfate from the anode chamber. By alternating electrokinetic transport and electrical resistance heating activation of peroxydisulfate for two cycles, the phenanthrene degradation efficiency in four evenly distributed wells between electrodes reached 75.4 %, 87.6 %, 92.3 %, and 94.4 %. With slight variations in soil morphology and structure, the electrokinetic transport coupled with electrical resistance heating activation of peroxydisulfate elevated the soil fertility index. The abundance and diversity of bacterial communities in treated soil recovered to above the original soil level after 15 days. Our findings may support the application of electrokinetic transport coupled with electrical resistance heating activation of peroxydisulfate as a promising green ecological technology for the in situ remediation of organic-contaminated soil.

Keywords: Electrokinetic transport; In situ chemical oxidation; Peroxydisulfate; Soil remediation; Thermal activation.