Study on the treatment of soil washing waste agent by the electro-Fenton method

Soil washing technology has been widely used for the remediation of heavy metal contaminated soil due to its short remediation cycle and significant remediation effect. However, during the washing process, a large amount of soil washing waste liquid is generated, which often contains refractory waste leaching agents, soil humus, and highly stable complex heavy metals, making it difficult to be directly treated to meet the standards using conventional flocculation precipitation methods. In this study, the washing waste agent from actual industrial contaminated soil containing Pb was taken as the research object, and a new type of cathode material - RGO@GF (graphene oxide loaded on graphite felt) - was prepared. Electro-Fenton technology was used to treat the washing wastewater containing IDS and Pb. The experimental results showed that under the conditions of an applied voltage of 2.5 V, initial pH of 3.0, electrolysis time of 8 hours, and oxygen flow rate of 100 mL/min, the removal rate of TOC in the leachate reached 56.29% and the removal rate of Pb in the leachate reached 98.91%, which was higher than that of conventional Fenton technology under the same conditions.