Integrated Electrochemical Technologies for Wastewater Treatment and Soil Remediation: Tackling Contaminants of Emerging Concern and Pathogens

Treated wastewater can help address water scarcity, but it’s crucial to test technologies that remove emerging contaminants of emerging concern (CECs) from both the effluent and potentially contaminated soils. This document combines findings from two works investigating the use of electrochemical oxidation (EO) and electrokinetic remediation (EKR) technologies to tackle CECs, including pharmaceuticals and Escherichia coli. For the treatment of effluent, EO showed removal efficiencies exceeding 90% for compounds such as sulfamethoxazole (SMX) and diclofenac (DCF) when using MMO/Ti circular mesh electrodes. EKR was applied to remove CECs, including SMX, DCF, and oxybenzone, from soils irrigated with effluent. It was shown that after being introduced into the soil by effluent irrigation, 20–100% of the CECs remained in the soil after 6 days. EKR improved the elimination of CECs by up to 20% compared to the control (without current), which depends on the contaminants’ distance to the electrodes. The simultaneous application of reversed electrode polarization and On/Off currents enabled a more uniform removal while maintaining soil characteristics, validating EKR as a viable in-situ remediation method. These findings highlight that integrated EO-EKR systems offer scalable, eco-friendly solutions for wastewater and soil remediation. On this topic, results from stakeholders’ perceptions of wastewater reuse are also presented to understand the needs and challenges of promoting an effective application. Subsequent studies should refine operating parameters, explore electrode configurations, and evaluate long-term environmental impacts to improve acceptance and effectiveness.