PhD Position (M/F): Theoretical study of the thermal stability of reactive working fluids for power plants

Job Description

Thesis Subject

Context:

This PhD thesis is conducted within the framework of the SPARTA program, supported by the French Government to foster industrial decarbonization and contribute to the achievement of carbon neutrality by 2050.

The objective of the SPARTA project is to develop a disruptive energy conversion system powered by a high-energy-density, non-fossil heat source, particularly Generation IV nuclear technologies. By using reactive working fluids instead of conventional water/steam systems, the project aims to significantly improve the compactness and efficiency of thermodynamic cycles beyond current state-of-the-art performance. The consortium brings together two industrial partners, NEEXT and EDF Arabelle Solutions, and one academic partner, LRGP.


Objectives of the thesis:

The potential reactive fluids considered for improving the efficiency of power plants must satisfy several stringent requirements. The expected performance enhancement relies on the occurrence of a reversible chemical reaction that evolves through equilibrium states along the different unit operations of the power cycle under in the effect of temperature and pressure variations. This reaction must be sufficiently fast to ensure that chemical equilibrium is reached almost instantaneously following changes in operating conditions. Furthermore, the reaction must remain unique and fully reversible so that the working fluid preserves its chemical integrity over repeated operating cycles.

However, many of the candidate compounds are organic species and therefore prone to thermal decomposition when exposed to elevated temperatures (typically between 200 and 400 °C, depending on the compound considered). The temperature and pressure conditions leading to decomposition vary significantly from one species to another, as they are strongly influenced by molecular structure and bond stability. Consequently, accurately determining the operating domain within which thermal decomposition does not occur is of crucial importance for the selection and safe utilization of reactive working fluids in advanced energy conversion systems.

This work will primarily focus on the theoretical investigation of the thermal decomposition of potential reactive working fluids, mainly organic acids, which have the ability to form dimers in both the gas and liquid phases through a reversible equilibrium reaction. The theoretical part of the project will involve the development of a predictive tool based on computational chemistry, enabling the extension of stability studies to a broader range of operating conditions. These models will be validated against experimental data acquired within this study.


Requirements:

We are seeking a highly motivated candidate holding a Master's degree in Chemical Engineering or Computational Chemistry. Chemoinformatic skills and experience are highly desirable. The candidate is expected to be proficient in Python language for which many chemoinformatic libraries are available (e.g., RDKit, Open Babel, etc...). Good communication skills in English, both written and spoken, are essential, together with a strong inclination toward teamwork and an enthusiasm for working in a multidisciplinary environment.

The PhD candidate will be involved in a strategic research project for which the expected outcomes are critical to its successful development and the continuation of the associated funding activities. As a result, a high level of commitment and excellence is expected, together with rigorous and high-quality scientific work.

Your Work Environment

About the Laboratory:

The Laboratoire Réactions et Génie des Procédés (LRGP, UMR CNRS 7274) is a joint research unit of the French National Centre for Scientific Research (CNRS) and the University of Lorraine, established on January 1, 2010, and located in Nancy, France.

The laboratory's overall scientific objective is to advance the understanding of process engineering in all its complexity. LRGP develops the scientific and technological knowledge required for the design, analysis, operation, and optimization of complex physicochemical and biological transformation processes involving matter and energy.

The laboratory brings together more than 300 members, including approximately 20 CNRS researchers, 80 faculty members, 45 engineers, technicians and administrative staff, and around 180 non-permanent staff members (research associates, 85 PhD candidates, postdoctoral researchers, and Master's students).

Research Environment:

The PhD project will be carried out within the **CiTherE** research group, which brings together specialists in chemical kinetics, thermodynamics, and chemical reaction engineering. The group's research focuses primarily on energy-related applications, with the objective of developing more efficient, sustainable, and environmentally friendly energy systems through an approach combining physical chemistry and process engineering.

The experimental and theoretical research conducted within CiTherE provides a unique multiscale framework, bridging the understanding and modeling of phenomena from the molecular level to the reactor and process scales.

The successful candidate will join the **Radical Kinetics** team, which has extensive expertise in the kinetics of pyrolysis, oxidation, and combustion reactions. The team's research covers a wide range of applications, including oil production and processing, combustion in engines and burners, pollutant formation, and the thermal destruction of hazardous chemical compounds.

Security Clearance:

This position is located in a research area subject to the French regulations on the protection of scientific and technical potential (*Protection du Potentiel Scientifique et Technique – PPST*). Consequently, in accordance with French regulations, the appointment of the successful candidate is subject to prior authorization by the competent authority of the French Ministry of Higher Education and Research (MESR).

Compensation and benefits

Compensation

2300 € gross monthly

Annual leave and RTT

44 jours

Remote Working practice and compensation

Pratique et indemnisation du TT

Transport

Prise en charge à 75% du coût et forfait mobilité durable jusqu’à 300€

About the offer

About the CNRS

The CNRS is a major player in fundamental research on a global scale. The CNRS is the only French organization active in all scientific fields. Its unique position as a multi-specialist allows it to bring together different disciplines to address the most important challenges of the contemporary world, in connection with the actors of change.

CNRS

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