Description du sujet de thèse

The prerequisite for the development of a solar AC regeneration process is a systematic laboratory-scale assessment of the performance of the regeneration process. This involves determining the most favourable operating conditions (irradiation wavelength, AC load, primary oxidant concentration, nature of the pollutants adsorbed, etc.) and understanding the fundamental principles of the mechanisms associated with the regeneration process. The aim is to develop protocols and implement advanced characterisation techniques that will make it possible to: (i) evaluate the possible effect of radical species on the characteristics of the AC (microporosity, surface chemistry); (ii) experimentally evaluate and model the efficiency and kinetics of regeneration of ACs saturated with molecules representative of families of emerging contaminants; (iii) evaluate the regeneration of saturated ACs after use in Jacobi Carbons' client drinking water production plants; all of this to provide a set of data enabling the dimensioning of the solar prototype. These studies will be carried out using two complementary methods: thermal activation of persulphate, which occurs at 60°C for the production of sulphate radicals, and photoactivation of hydrogen peroxide for the production of hydroxyl radicals. Following these laboratory studies, the second stage will involve validating, for the most effective option and for commercial CA from drinking water treatment plants, regeneration under natural solar radiation. This stage will be carried out by means of outdoor tests on a dedicated pilot operating on a small but representative scale, with quantities of the order of 1 to a few kg of AC.
All the characterisation of the carbonaceous material and all the studies on the persulphate option will be carried out at the ICMN (Orléans), the host laboratory. Regeneration tests with hydrogen peroxide will be carried out in part at the CEMHTI (located 10 minutes' walk away on the same CNRS campus). The implementation and characterisation of the solar regeneration process will be carried out at the Laboratoire des Procédés, Matériaux et Energie Solaire (PROMES) in Perpignan during a 6-month stay.

Contexte de travail

This PhD is part of the SACRE (Towards Solar Activated Carbon REgeneration) research programme funded by the French national research agency (ANR-24-CE51-4334). This 4-year programme began in January 2025. It brings together 5 academic laboratories: ICMN Orléans, CEMHTI Orléans, HYDROSCIENCES Montpellier, ICOA Orléans and PROMES Perpignan, with expertise covering the fields of carbonaceous materials and their characterisation, advanced oxidation processes and mechanisms, micropollutants and their analysis and quantification, and solar engineering. Jacobi Carbons Groups France, a global producer and supplier of activated carbons for a wide range of applications including wastewater treatment and water purification, is also part of the SACRE PRCE (Collaborative Research Project - Enterprise) consortium.

Contraintes et risques

No particular constraints