Structural analysis and Imaging

Biomass conversion into chemical products and intermediates is increasingly being adopted to reduce the carbon footprint of the industry concerned. Among biomass-based resources, sugars are extremely attractive since they contain a lot of functional groups enabling their conversion to products of interest (alcohols, acids, etc.). For example, through fructose dehydration, it is possible to obtain 5-hydroxymethylfurfural (5-HMF), a molecule that can be used to produce polymers. Since the conversion of fructose to 5-HMF is catalyzed by Brønsted acids1, liquid acid catalysts in solution are currently used, but without the possibility of recycling this catalyst. The development of a solid acid catalyst is thus crucially important...

For the last ten years or so, geologists have been fascinated by the natural hydrogen (H2) emitted within “cratons”, in the heart of continents. While its presence in subsurface has been identified in many places around the globe, it remains to be ascertained whether the use of this decarbonized energy source is likely to be economically viable. To answer this question and then identify the drilling sites with the greatest potential, large-scale quantification of this resource requires the use of modelling. (...) This PhD research set about examining the issue, taking as its subject the North American Midcontinent Rift System (MRS) composed of ancient rocks (over 1 billion years old) and extending over thousands of kilometers.

Metal- and ceramic-based solid foams are porous structures that have begun to be used relatively recently in the field of chemical processes although they have been the focus of research at IFPEN for a few years already. Due to their 3D texture, made up of a multitude of juxtaposed spherical cavities (familiar in the field of heterogeneous catalysis), these structures are highly porous (around 70-80%) and have a large specific surface area. On the face of it, this is associated with good external transfer performances...

In chemical conversion processes implementing heterogeneous catalysis, the active phase, which accelerates molecular conversions, is often deposited on a porous support. Most of the time, this support has a large internal surface area, making it possible to host a large number of active sites within a small volume. Very often, the porous support is alumina, which needs to have adequate mechanical and thermal resistances and enhance mass and heat transfer. These properties are highly dependent on the texture of the support, which itself stems from its production process...

Processes using heterogeneous catalysis require the design and development of innovative materials, with controlled mechanical and textural properties, to produce effective catalyst supports. The porous microstructure of these supports has a significant impact on the performance of the supported catalyst, since it strongly affects the support’s mechanical resistance and transport phenomena...

While macroscopic models combined with experimental analysis of porosity are well established for geometrically simple pores, hierarchized and disordered microstructures defy existing frameworks and call into question conventional interpretations. We proposed a digital framework to help overcome this challenge, taking into account morphology, connectivity and pore size distribution...

In the context of the energy transition, it is expected that oil production will decrease at the same pace as the development of low-carbon energies and people’s evolving needs in this area...

In catalytic processes, an active phase is necessary to accelerate the transformation of the molecules in the fluid treated. Most of the time, this catalytic agent is placed on a porous support with a large internal surface area, making it possible to host a large number of active sites within a small volume...

The increase in the level of atmoshpheric CO2 and the resulting climate change are a global concern. Despite this, the use of fossil fuels continues to grow, in response to high energy demand. Combined with storage and CO2 conversion solutions, Chemical Looping Combustion processes (CLC) offer a medium-term solution to reducing the impact of energy production from fossil fuels, or even biomass...