Towards carbon circularity via waste py-oil upgrading: understanding and predicting matrix effects



Scientific disciplines

Chemical Sciences

Research direction

Process Design and Modeling

Affiliate site


The PHD project is placed in the context of recycling and recovery of hydrocarbon products such as tires and used plastics. A possible way of reprocessing concerns the py-oils resulting from these products. These, although they can be considered as unconventional, have a calorific value at least similar to current fuels and are chemically stable. They can be directly or indirectly recycled by hydrotreatment and fractionation stages into fuels of interest.
Nevertheless, as they are new feedstocks, these py-oils contain new molecules for which it is necessary to know the reactivity and the inhibition power, especially during the hydrotreating step. The objective of the thesis is therefore to identify the most refractory compounds and to estimate their reactivity. A kinetic model will be developed considering the inhibition between all reactions. One type of compound will be particularly targeted: nitrogenous molecules because they are poison regarding the cracking catalyst. 
To achieve this objective, this thesis aims to develop a methodology to evaluate the reactivity of py-oils, first in batch reactors, with synthetic mixtures, which will allow to establish a preliminary kinetic model. Then to refine the parameters of the model for an implementation in a continuous reactor as it could be the case for an application in industrial processes like those existing. Advanced analytical techniques will be used to characterize the effluents, as well as numerical, mathematical and chemical engineering models to try to identify the various contributions to the intrinsic kinetics as well as to the global kinetics of transformation of the impurities present in the py-oils.

Keywords: Chemical Engineering, Process System Engineering, Kinetics, catalysis, New Energies, recycling, upgrading, Batch and continuous reactors

  • Academic supervisor    Professor, THYBAUT Joris, Laboratory for Chemical Technology, Ghent University, ORCID : 0000-0002-4187-7904
  • Doctoral School    Ghent University,
  • IFPEN supervisor    PHD, CELSE Benoit, R123,, ORCID : 0000-0002-2503-6734
  • PhD location    IFP Energies nouvelles, Lyon, France
  • Duration and start date    3 years, starting in fourth quarter 2023
  • Employer    IFP Energies nouvelles, Lyon, France
  • Academic requirements    University Master degree in Process and System Engineering, Chemical Engineering
  • Language requirements    Fluency in French or English, willingness to learn French
IFPEN supervisor:
CELSE Benoit
PhD student of the thesis:
Promotion 2023-2026