Chemical valorization of plastic wastes

Stage M2
CEA Saclay, Site de l’Orme des merisiers (91) Essonne, France
January 30 2025
January 1 2025
6 month
2025-chemical-valorization-of-plastic-wastes-en

Domain, Specialties : CHEMISTRY
Keywords: Homogeneous catalysis; Chemical depolymerization; plastics

Research Unit : NIMBE/LICSEN

Summary

The aim of this project is to synthesize organometallic catalysts and test them in the reductive depolymerization of plastics.

Full description

Since the 1950s, plastics have gradually replaced traditional materials (wood, metal, concrete) in many sectors, becoming indispensable thanks to their low cost and adjustable properties. Today, 460 million tons of plastics are produced each year, and more than 9 billion tons have been produced since the end of the Second World War. The production of these polymers, based on oil, emits massive amounts of CO2, contributing to global warming, and their use, mainly for very short period of time, generates a stream of waste that causes permanent pollution. How can we control the end-of-life of these wastes and integrate them into a more virtuous, circular economic system? At the end of their life, plastics should no longer be landfilled or incinerated (energy recovery), but rather recovered as a potentially sustainable source of organic chemicals. This is the purpose of chemical recycling, which involves developing effective processes to treat all types of plastics (carbon-based, oxygen-based, nitrogen-based such as polyethers, polyesters and polyamides, etc.) to recover their carbon content.

The aim of this project is to use molecular complexes of d and f-metals to depolymerize oxygenated (esters, carbonates, etc.) and/or nitrogenated (polyamides and polyurethanes) plastics with mild reducing agents under reducing conditions. We will also study the cleavage, catalytic or not, of these polymers in the presence of silylated reagents or acid derivatives. The cleavage of these polymers, ideally into their monomers or close derivatives, will be carried out by cleavage of the carbon-oxygen and carbon-nitrogen bonds.

References:

  • P. Shaver et al, Chem. Rev. 2024, 124, 5, 2617–2650 ; A. P. Dove et al, Polym. Chem., 2019, 10, 172-186 ; E. Y.-X. Chen et al, Green Chem. 2017, 19, 3692–3706.
  • Feghali, T. Cantat, ChemSusChem 2015, 8, 980-984;
    L. Monsigny, J.-C. Berthet, T. Cantat, ACS Sustainable Chem. Eng. 2018, 6, 8, 10481-10488;
    M. Kobylarski, J.-C. Berthet, T. Cantat Chem. Commun. 2022, 58, 2830–2833;
    X. Liu, M. Kobylarski, J.-C. Berthet, T. Cantat Chem. Commun. 2023, 59, 11228–11231;
    M. Kobylarski, L. J. Donnelly, J.-C. Berthet, T. Cantat Green Chem. 2022, 24, 6810–6815

Location

CEA Saclay, (91) Essonne, France

Internship conditions

  • Internship duration: 6 months
  • Level of study: Bac+5
  • Training: Master 2
  • Continuation in PhD thesis: Yes
  • Application deadline: 1 janvier 2025

Experimental skills

Useful methods and technics:
Students will develop their skills in organic and organometallic synthesis, working in an inert atmosphere (argon- vacuum lines, glove boxes) and in the analysis of chemical compounds (NMR, GC-MS, IR, X-rays).

Langue : Anglais

Links

Supervisor

Jean-Claude BERTHET
Phone: 01 69 08 60 42
Email :

Head of the laboratory

Thibault CANTAT