Description du sujet de thèse

As part of an Interreg project FWVL, this PhD thesis focuses on circular economy strategies applied to plastic materials originating from complex waste streams. The goal is to develop and optimize decontamination processes that enable the safe reuse of these materials as new raw resources.
The doctoral researcher will work on:
• The physical treatment of contaminated polymer mixtures (irradiation, extraction, etc.);
• The study of degradation kinetics and the identification of resulting by-products;
• The characterization of materials before and after treatment (chemical, thermal, and mechanical properties);
• The valorization of decontaminated polymers and the assessment of their potential for recycling.
The work will benefit from comprehensive analytical facilities and close collaboration with several academic and industrial partners involved in the project.

Contexte de travail

This PhD project (doctoral school SMRE) will take place within the “Recycling and Functionalization Processes” (PReF) team of UMET (Unité Matériaux et Transformations – UMR 8207, CNRS/University of Lille). Among its four main research orientations, the PReF team leads a thematic area focused on “Materials Recycling”, which covers:
• the development of decontamination processes for end-of-life materials (e.g. UV-Visible irradiation, electron beam treatments),
• the recycling, reuse, and recovery of WEEE (Waste Electrical and Electronic Equipment).
These topics address major environmental challenges and are supported by multidisciplinary collaborations with both academic and industrial partners in fields such as chemistry, physics, materials science, electronics, and industrial production.
The PReF team has established recognized expertise in the design of photolytic reactors, operating in static or dynamic mode, with the aim of developing solvent-free, dry processes. These systems were successfully implemented during the interreg FWVL VALBREE project, where UMET demonstrated a reduction of more than 85% in the content of brominated flame retardants (BFRs), persistent organic pollutants found in model polymer mixtures.
Building on this experience, the proposed PhD will contribute to an interreg project by exploring eco-friendly extraction and decontamination processes, and supporting the formulation of new sustainable recycled materials.

Candidate Profile:
• Master's degree (MSc or Engineering diploma) in Materials Science, Physical Chemistry, Analytical Chemistry, Polymer Science, or related fields.
• Strong experimental skills and interest in polymer characterization, degradation processes, or sustainable materials.
• Prior experience with spectroscopic/chromatographic techniques and/or polymer processing would be a plus.
• Good communication and writing skills. Fluency in English (B2 level or higher) required.
• Motivated, curious, and ready to engage in multidisciplinary, collaborative research.

Le poste se situe dans un secteur relevant de la protection du potentiel scientifique et technique (PPST), et nécessite donc, conformément à la réglementation, que votre arrivée soit autorisée par l'autorité compétente du MESR.

Contraintes et risques

Technical and Experimental Constraints:
• Handling of potentially hazardous substances, requiring strict adherence to laboratory safety rules (use of personal protective equipment (PPE), working in fume hoods, management of chemical waste).
• Use of specialized equipment (irradiation, chromatographic analyses, spectroscopy, etc.), requiring specific technical training and access to these tools, which may be limited in availability.
• Execution of long and complex experiments, involving rigorous planning, repeatability of measurements, and the adaptation of protocols based on intermediate results.