Skip to Main content Skip to Navigation
Theses

Contribution of NMR and Raman imaging for modeling and rationalization of the impregnation process of metallic precursors in porous media

Abstract : The objective of this work is to characterize the impregnation step in terms of physical phenomena (capillarity and diffusion) and chemical phenomena (surface interaction) in order to identify the key descriptors of this step in order to improve the preparation hydrotreating catalysts. This involves monitor spatial and temporally the transport of the species in the impregnation solution within the porosity, more particularly in the case of Ni(Co)MoP/?-Al2O3 catalysts preparation.An original MRI approach has been developed to follow in-situ the impregnation step from a solution of mixed nature with more than one metal precursor in the presence of an additive. MRI provides access to the spatial distribution of all species within the catalyst with a spatial resolution of 39 × 39 µm. Raman imaging allows an identification of the chemical nature of the species in solution with a spatial resolution of 16.2 × 16.2 µm.First, the phenomena involved in the impregnation of model solutions composed of Ni (or Co), were studied by modifying the parameters of the solution. These experiments were then used as the basis for the development of a mathematical model to rationalize the impregnation step. In a second part, this study was extended to the preparation of hydrotreatment catalysts. Several phenomena have been evaluated here, notably the impact of the presence of phosphorus on the transport of Mo species, possible competition of adsorption between P, Co and Mo and the effect of the presence of citric acid.This study allows a better control of the impregnation step and thus of the distribution profile of the active phase, which has an impact on the catalytic performance
Document type :
Theses
Complete list of metadatas

Cited literature [183 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-01779449
Contributor : Abes Star :  Contact
Submitted on : Thursday, April 26, 2018 - 3:49:11 PM
Last modification on : Tuesday, January 22, 2019 - 3:51:44 PM

File

TH2017DUARTEMENDESCATITALEONOR...
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-01779449, version 1

Collections

STAR | IFP

Citation

Leonor Duarte Mendes Catita. Contribution of NMR and Raman imaging for modeling and rationalization of the impregnation process of metallic precursors in porous media. Catalysis. Université de Lyon, 2017. English. ⟨NNT : 2017LYSE1262⟩. ⟨tel-01779449⟩

Share

Metrics

Record views

267

Files downloads

153