Synthesis of Si/Al gradient zeolites and their use in adsorption, separation and catalysis

Zeolites are crystalline and microporous aluminosilicates. The perfectly controlled porosity and the presence of charges due to the presence of aluminum in the framework provides to these materials specific properties which give rise to very diverse applications (ion exchange, separation, adsorption, catalysis). These materials are beginning to be used more and more in industrial processes in the presence of water and temperature. For this it is necessary to have an active and stable material under hydrothermal conditions. The active site in a zeolite is usually a Bronsted acid, created by the presence of Al in its structure, for which there is strong competition between water and the molecules of interest. It is necessary to prepare zeolite crystals that exhibit a diffusional barrier to water while allowing easy access to molecules of interest at active sites.
The objective of this thesis are the synthesis of active and stable zeolites under hydrothermal conditions by creating an Si/Al composition gradient and the understanding of the conditions necessary for their preparation. The targeted approach combines the synthesis, characterization and testing of the materials obtained.
Through this thesis, the candidate will obtain a solid training in the synthesis and post-treatment of zeolites as well as in the characterization of crystallized porous solids. In addition, he will be confronted with the problems of the evaluation of such solids in catalysis and separation.

Keywords: zeolite, composition gradient

• Academic supervisor    Dr., TUEL Alain, Institut de recherches sur la catalyse et l’environnement de Lyon, IRCELYON, ORCID : 0000-0001-7610-4074
• Doctoral School    ED206 - Ecole doctorale Chimie, Procédé, Environnement, https://www.universite-lyon.fr/recherche/doctorat/ecoles-doctorales/ed-206-chimie-procedes-environnement-4399.kjsp
• IFPEN supervisor    Dr., HARBUZARU Bogdan Vasile, Divided Materials Egineering Department, bogdan.harbuzaru@ifpen.fr, ORCID : 0000-0001-9063-1874
• PhD location    - IFP Energies nouvelles, Lyon, France - IRCELyon, Lyon, France
• Duration and start date    3 years, starting in fourth quarter 2021
• Employer    IFP Energies nouvelles, Rueil Malmaison, France
• Academic requirements    University Master degree in chemistry
• Language requirements    Fluency in French or English, willingness to learn French
• Other requirements    Basic knowledge in XRD, N2 adsorption, MAS NMR.