Nom de l'entreprise / du laboratoire: Laboratoire GREMI (Groupe de Recherche sur l'Energétique des Milieux Ionisés), UMR CNRS / Université d'Orléans 7344

Subject:

Current environmental challenges, including aquatic pollution and rising energy demands, call for innovative solutions that both enhancewastewater treatment efficiency and enable energy recovery while minimizing carbon footprints. Non-thermal plasma processes offer apromising approach in this context. Plasma reactors are highly effective at generating reactive oxidizing species (O, OH, O₃, …) and havedemonstrated applicability for treating both gaseous and liquid pollutants.
The GREMI laboratory, specializing in plasma and laser processes, conducts advanced research on these topics within its “Treatment andValorization of Effluents” axis. The main objective of this PhD project is to explore the potential of non-thermal plasma sources atatmospheric-pressure for the treatment of liquid effluents with high volatile organic compound (VOC) content, targeting energy recovery.These solutions representative of Industrial wastewater streams with high VOC concentrations (>1% v/v) are particularly suitablecandidates due to their rich carbon and hydrogen content, offering significant potential for energetic gases production with high contents inmethane and hydrogen. This experimentally focused project will address three complementary research axes:
1°) Gas-phase analysis: Gas composition at the plasma reactor outlet will be assessed using multiple techniques, including gas analyzers,FTIR, and GC/TCD-FID-MS. These measurements, combined with plasma electrical diagnostics, will allow evaluation of energy gasproduction efficiency (g/kWh). Various plasma reactor configurations available at GREMI including gliding arc discharges, point-to-pointdischarges, plasma torches will be tested under different operating conditions (carrier gas type and flow, liquid flow, mixture composition) toidentify optimal conditions for CH₄ and H₂ production.
2°) Plasma-phase characterization: Optical emission spectroscopy (OES), potentially coupled with FTIR, will be used to characterize reactivespecies, temperatures, and plasma densities. Correlating these parameters with gas production performance will help elucidate themechanisms driving methane and hydrogen formation in this process.
3°) Liquid-phase analysis: The treated liquid effluent will be analyzed by UV-Vis spectrophotometry, GC/MS, and HPLC to quantify residualpollutants and by-products. This will provide a comprehensive assessment of pollutant degradation and allow evaluation of the ecotoxicityof treated solutions.
Overall, this project aims to optimize plasma-based processes for energy recovery from industrial wastewater while advancing fundamentalunderstanding of plasma/liquid interactions.

Required Technical Background
Applicants must hold a Master’s degree (MSc) or an Engineering degree and demonstrate a strong background in several of the following areas:
• Physicochemical analytical techniques (UV–Vis spectrophotometry, IR spectroscopy, gas and/or liquid chromatography)
• Analytical chemistry
• Solution chemistry
• Plasma physicochemistry
• Experimental work on laboratory-scale setups
• Modeling of plasma–liquid interactions
Experience in imaging, advanced spectroscopy, or electrical diagnostics will be considered a strong asset.

Additional Skills and Qualifications
• Advanced proficiency in French (≥ B2)
• Advanced proficiency in English (≥ B2)
• Strong motivation for experimental research, particularly in plasma–liquid interactions
• Excellent written and oral communication skills
• Ability to work rigorously and creatively

To apply: https://adum.fr/as/ed/voirproposition.pl?site=adumR&matricule_prop=71205

Deadline: April 10, 2026