Missions

24-month fixed-term contract, renewable for 6 months.
The cement industry, which alone accounts for around 5% of global CO2 emissions, is undergoing a profound transformation in line with the industry's decarbonization requirements. Low-carbon cements are based on the partial substitution of clinker, the main source of CO2 emissions of the cement industry, with slags. Slags are glassy phases formed at high temperatures during the reduction of iron ore. Like volcanic glass, they take the form of an amorphous silicate solid with a few crystallized phases (silicates and calcium aluminosilicates, spinels, etc.). Changes in manufacturing processes and the decarbonization of the steel industry, from blast furnace slags to electric arc furnace slags, are leading to changes in the composition of slags. These new materials present many challenges and opportunities for their use. These new residues contain mineral phases that are more or less reactive and can affect the hydration of cementitious phases or the release of trace metals into the environment.
The objective of this research project is to understand how the physicochemical properties of electric arc furnace slag are related to their reactivity, hydration, and therefore to the properties and durability of the concrete produced, but also to assess their environmental compatibility in relation to the presence and remobilization of trace metals in the glass phase.
To do this, the proposed work will consist of finely characterizing the physical-chemical properties of the slags, and evaluating their role in the hydration of the cementitious phases. In particular, the research work will focus on the following areas:
• Detailed characterization (chemical, mineralogical, and microstructural) of slags
• Speciation and evaluation of the mobility of iron and trace metals (V, Cr, Mo) in slag and hydrated cement;
• Understanding the mechanisms of stabilization or leaching of trace metals in slag.
To this end, various chemical, mineralogical, and structural characterization techniques will be used: LA-ICP-MS, HT-XRD, XRF, X-ray absorption spectroscopy (XANES, EXAFS), X-ray microtomography, and 3D X-ray diffraction (s3DXRD).
Candidates should submit a detailed CV, a cover letter, and a short one-page research proposal on the proposed topic online.

Activités

The researcher will be responsible for the following activities:
- Bibliographic analysis: conduct a review of the current scientific literature on the link between chemical composition, physicochemical properties of slag, and reactivity to hydration of electric arc furnace slag.
- Mineralogical characterization and speciation of trace metal elements (Fe, Cr, Mo) in non-activated and activated slag.
- Characterization of the hydration mechanisms of cements in which these slags are incorporated.
- Synchrotron experiments
- Teamwork on scientific promotion: collaborating with the team to write publications and present results at international conferences.
- Co-facilitation of the collaborative research network in place in the associated research project.

Compétences

- Interest in issues and challenges related to industrial processes, material sustainability, and environmental risks.
- Thesis in physical chemistry of materials, environmental geosciences, or environmental engineering
- Knowledge of tools and techniques for characterizing solids and fluids.
- Previous experience in the use of tools exploiting X-ray-matter interactions would be an advantage.
- Ability to contribute ideas in a multidisciplinary team.
- Good oral and written communication skills and experience.
- Fluency in English (written and spoken) is essential for interacting with project collaborators.

Contexte de travail

The successful candidate will work at the Géosciences Environnement Toulouse laboratory (UMR CNRS/University of Toulouse/IRD/CNES), within the “Experimental Geosciences, Interface Reactivity and Biogeochemical Cycles” research team.
The position is available from March 2026 on a full-time basis as part of the ambitious European project EIC Pathfinder Challenges 2024 ECO-SLAG-CEM funded by Horizon Europe, which aims to optimize the compatibility of electric arc furnace slag for low-carbon cements and in which the Toulouse Environmental Geosciences Laboratory is a partner. Close collaboration with the various partner teams and associated industries (ECOCEM, FEHS, ETH, LMDC, AM) is expected.
The Toulouse Geosciences Environment Laboratory (GET) is one of the laboratories of the Midi-Pyrénées Observatory. GET has a staff of 250, including around 150 researchers and teacher-researchers. It offers a multidisciplinary environment comprising geologists, chemists, physicists, biologists, modelers, and sociologists. GET has a large number of experimental, analytical, and IT platforms to ensure the smooth running of the project.
https://www.get.omp.eu/

Travel to major research facilities in Europe or to other laboratories will be required, as will participation in workshops, project coordination meetings, and/or national and international conferences.

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

Missions in France and/or abroad are to be expected.