Coupling radical and catalytic plastic cracking : Unveiling mechanisms towards better recyclability

As plastic waste defines the Anthropocene, efforts towards the development of recycling technology are ramping up. For polyolefins (PO), common packaging materials, the available technologies of mechanical recycling and of pyrolysis (thermal conversion) have several drawbacks and can process only a fraction of waste. A promising alternative pathway for PO recycling has been explored in which the PO conversion is enhanced by the presence of H2S, which promotes thermal cracking. When this is coupled with a well selected heterogeneous catalyst, the products obtained can selectively be optimized towards better recyclability. 
The objectives of the research are: first, to elucidate the thermal cracking mechanism of polyolefins in the presence of H2S and second, to optimize the coupling of the thermal mechanism with a catalytic mechanism by adding a catalyst. The work will be centered on the realization of plastic conversion tests in a dedicated unit, product characterization and interpretation of results. The thus obtained data and insights will be used to build a reaction mechanism and its modeling by adapting existing methodologies.
This research will provide valuable fundamental understanding of the mechanism of polyolefin cracking in presence of H2S both experimentally and theoretically. This knowledge is absent from the current literature and is essential to the development of an alternative and robust PO recycling technology. 
The work will take place at IFPEN, mostly in Solaize with some time spent in Rueil, a research entity with significant experience in the study of complex molecule conversion, catalytic systems, reaction mechanisms and kinetic modeling. The project is developed in collaboration with CP2M laboratory in Villeurbanne specialized in polyolefin synthesis, recycling, and analysis. 

Keywords: plastic, recycling, polyolefins, conversion, kinetic modeling, hydrocracking, hydrogen, sulfur

• Academic supervisor    Dr Elodie DEVERS, IFPEN
• Doctoral School    ED206 Chimie de Lyon, Université Claude Bernard Lyon 1
• IFPEN supervisor    Dr Ana Teresa FIALHO BATISTA, ORCID : 000-0001-9905-3898
• Co-Supervisor    Dr Vincent MONTEIL, CP2M, ORCID: 0000-0003-3530-1789
• PhD location    IFPEN, Lyon, France 
• Duration and start date    3 years, starting in the fourth quarter 2024
• Employer    IFPEN
• Academic requirements    University Master degree in chemical sciences, chemical engineering
• Language requirements    Fluent in English , willingness to learn French
• Other requirements    Liking for laboratory work; Knowledge of numerical simulations appreciated; Programming skills appreciated

For more information on the subject feel free to contact the IFPEN supervisor.
To apply, please send your cover letter and CV to the IFPEN supervisor indicated below.