development of a NET (Negative Emission Technologie) process combining CO2 capture and hydrogenation into synthetic fuel
Until recently, CO2 capture technologies were developed separately from CO2 utilization technologies, even though coupling the CO2 desorption stage with the chemical transformation of CO2, which is generally exothermic, would yield significant energy savings.
The first coupled solutions have recently been proposed, but they are mainly at moderate temperatures (100-180°C) [1], or even recently close to 225°C [2].
The objective of this doctoral thesis is to study, both experimentally and theoretically, a coupled system in the 250-325°C temperature range that allows via Fischer-Tropsch-type catalytic hydrogenation the direct production of higher value-added products
Optimising the enzymatic degradation of polylactic acid (PLA) to produce biohydrogen (BioH2) through photofermentation.
This thesis project presents a novel method of producing biohydrogen (BioH2) through the enzymatic breakdown of polylactic acid (PLA), a bioplastic which is challenging to recycle. The aim is to optimise the hydrolysis of PLA into lactic acid, which can be metabolised directly by purple non-sulfur bacteria (PNSB) to produce BioH2 in anoxic conditions. The work will entail selecting high-performance esterases in collaboration with Génoscope CEA, expressing them in soluble form in model hosts such as E. coli, yeasts and PNSB, and optimising reaction conditions such as pH, temperature and concentration to maximise lactic acid production. The second phase will focus on enhancing photofermentation in a photobioreactor (PBR) with advanced control systems (LED, AI and CFD). Funded by the CEA and PUI Grenoble Alpes, this project is part of a circular economy approach, aiming to develop a scalable process for converting PLA waste into renewable energy in line with the challenges of the energy transition.
Physicochemical Properties of Antimony-containing Photovoltaic (PV) Glass
The proposed PhD thesis is part of the ANR GRISBI project (2026–2030), which aims to optimize the recycling of glass from photovoltaic (PV) panels. These glasses, predominantly manufactured in China, are doped with antimony oxide (Sb2O3) to ensure high transparency while keeping production costs low. However, the presence of antimony currently prevents the recycling of these glasses within the European flat glass industry, which would otherwise greatly benefit from this secondary raw material to reduce its environmental footprint — particularly its greenhouse gas emissions, in line with the carbon neutrality targets set by the Paris Agreement (2015). To make the recycling of PV glass into flat glass production feasible, it is therefore essential to gain a deeper understanding of the physicochemical behavior of antimony in glass, and more generally, within the float process, which involves a hot glass / liquid tin interface.
The core scientific objective of the PhD is to determine the redox equilibria between the multivalent species present in PV glasses, in particular the Sb2O3/Sb and Fe2O3/FeO couples. The work will involve preparing glasses with different Sb2O3 contents, then determining the mechanisms of antimony incorporation into the glass structure, as well as the temperature and oxygen partial pressure (pO2) conditions leading to the reduction of Sb³? to metallic Sb°. Experimental results, based on advanced materials characterizations such as SEM, XRD, EXAFS, and XANES, will be used to enrich thermodynamic databases and to develop a methodology enabling the recycling of Sb-doped PV glasses in flat glass production.
The PhD will be conducted at CEA Marcoule, in collaboration with IMPMC (Sorbonne Université) — two laboratories internationally recognized for their expertise in glass science. All glass samples will be synthesized by the PhD student, and their characterization will primarily rely on facilities available at CEA and IMPMC.
A background in Materials Science is required. This research project will provide the PhD candidate with the opportunity to develop strong expertise in applied glass science and industrial recycling technologies.