Description du sujet de thèse

Context: The recovery of metals of interest present in electronic waste (WEEE) is at the heart of current issues in terms of recycling and securing supplies. Our teams (LHYS at the ICSM and LPSD at the DMRC) are respectively focused on precious metal recovery, and development of new separation processes. In this context, we studied the selective extraction of palladium from leachates (solutions resulting from the more or less selective dissolution) of WEEE, and showed that some derivatives of the malonamide family may have excellent properties (affinity and selectivity). These molecules can be integrated on solid support, applying the methodologies developed for the decontamination of radioactive effluents. The first results obtained have led to a patent application, and the application of prepared resins for the treatment of industrial effluents is being studied in the laboratory.
Project: The aim of this PhD thesis is to study the mechanism of selective recovery of different platinum group metals, as well as issues related to the interactions between these cations of interest and other ions present in the industrial effluents targetes. In particular, the interactions between different metal cations and the associated redox reactions will be the subject of a detailed study.
The work will consist in preparing the resins, and studying their functioning in simulated and then real environments. Several tasks will therefore have to be considered:
- The organic moieties specific to the target elements will be prepared in a few simple and well-described steps from commercial raw materials;
- Solid supports will be selected from the available industrial products;
- Functionalized materials will be prepared and completely characterized (SEM, BET, functionalization yield);
- The decontamination capabilities of materials on simulated effluents will be evaluated, according to the different parameters (composition of multimetallic solutions, functionalization rate and nature, temperature) and the recovered metals will be quantified (ICP-AES, TOC);
- The mechanism of recovery of platinoids will be fully elucidated, with emphasis on the speciation of recovered metals (in solution and solid);
- The limitations and scope of the materials according to the different industrial effluents available will finally be established.
For this study, the LHYS and LPSD laboratories have means of elaboration and characterization of grafting agents (liquid NMR, UHPLC/MS) characterization of solids (SEM, laser granulometry, BET, TGA, solid NMR) and chemical analysis in solution (ion chromatography, ICP-AES). All work will be conducted at the Marcoule nuclear site, on ICSM and HERA facilities.
This subject is addressed to a chemical engineer or equivalent, preferably graduated with a Research Master, with good knowledge of general chemistry, and attracted by an applied subject, at the interface between molecular chemistry, coordination chemistry, solution chemistry, analytical characterization and chemical engineering.

Contexte de travail

The thesis will take place at the Institut de Chimie Séparative de Marcoule (ICSM), at LHyS, the Laboratory of hybrid systems for separation (https://icsm.fr/lhys.html), which seeks to develop new approaches in the field of circular economy, Producing high value metal compounds from waste, taking into account economic and ecological constraints. The thesis is funded by the CNRS, as part of a collaborative project involving a recycling SME and the CEA: The MOTRIS project (Innovative Processing and Recycling of Critical and Strategic Metals), carried out by the company Sovamep based in Muret (Haute-Garonne), was selected as part of the FRANCE 2030 plan launched by the Ministry of Industry. This ambitious project aims to modernize the company's titanium and electronic card recycling chains, in order to effectively recycle industrial waste, thus contributing to the circular economy and reducing dependence on imported raw materials.

Contraintes et risques

Good knowledge of risks associated to the handling of chemical reagents is suitable.

Informations complémentaires

Send CV and motivation letter