Emmanuel Mousset has his expertise in developing advanced electrochemical processes for environmental applications, e.g. soil remediation and wastewater treatment. He got his PhD under supervision of Prof. M A Oturan in the framework of Erasmus mundus ETeCoS3 programme. As tenured CNRS researcher expert in the field, he has been invited in several conferences. He developed the kinetics of primary soil pollutant and the intermediates have been monitored and modeled which allowed predicting the evolution of these molecules. He demonstrated that this kinetics of pollutants degradation depend on the kind of washing agent employed (i.e. its chemical structure) to extract the pollutant from the soil. He also highlighted the ecotoxicity and biodegradability enhancement of the soil washing effluent treated by advanced electrochemical treatment after a certain electrolysis time. From this approach, new scientific and technological insights have emerged and have been patented and awarded.
Statement of the Problem: The remediation of polluted soil and sites is a major of concern not only for the consequence on the ecosystem but also for the contamination of groundwater as resource of drinking water. In this context, many studies have been devoted to find the most cost-efficient solution for soil remediation. Most of the organic pollution is composed of aliphatic hydrocarbons and polycyclic aromatic hydrocarbons (HAPs) but most of them are not biodegradable, which make not efficient enough the biological treatment. Physical techniques only contain the pollution but does not eliminate it while thermal treatment still remain expensive and denature the soil composition. Chemical oxidation methods have been proposed as well, but the addition of oxidants into the soil make the technique uncertain regarding the degradation yield and the hazardous oxidation by-products that can be formed.
Methodology & Theoretical Orientation: Soil washing (SW) and soil flushing (SF) technology using agents to extract and solubilize the pollutants have emerged and have shown promising results. Since these methods only transfer the pollution from soil matrix to liquid matrix, a post-treatment is required. The combination of SW/SF with electrochemical advanced oxidation process (EAOP) have been therefore proposed. EAOP have the advantage to not require the addition of oxidant that are produced continuously and in situ through electrochemical reactions.
Findings: Three major insights emanate from this combination: the surfactant structure has an importance in the pollutant degradation efficiency and the reusability of the washing agent, the integrated process can be performed at neutral pH and without addition of iron source for Fenton reaction, and the biodegradability enhancement with electrolysis time of SW/SF solutions.
Conclusion & Significance: These results gave new possibility of soil remediation by minimizing the use of reagent and by maximizing the pollutants degradation rates and yields.