| Pacific Rim Symposium on Surfaces, Coatings and Interfaces (PacSurf 2018) | |
| Energy Harvesting & Storage | Monday Sessions |
| Session EH-MoE |
| Session: | Process |
| Presenter: | Anne-Félicie Lamic-Humblot, Sorbonne Université, France |
| Authors: | A.-F. Lamic-Humblot, Sorbonne Université, France C. Bara, Solvay R. Garcia de Castro, Sorbonne Université, France E. Devers, IFPEN G. Pirngruber, IFPEN M. Digne, IFPEN X. Carrier, Sorbonne Université, France |
| Correspondent: | Click to Email |
Since 2009, the sulphur content need to be reduced to 10 ppm in gasoline. In order to achieve this goal, hydrodesulphurisation process is efficient for now, using sulfided molybdenum (doped or not by cobalt) deposited on alumina.
In order to optimize this process, a molecular-scale understanding of the adsorption of the active phase (metal ions) is of fundamental importance. However, this objective is difficult because of the high surface area developed by the support (g-alumina) and the large number of exposed sites. One way to simplify the system is to use oriented single crystals of alumina presenting a lower number of sorption sites and well defined surface sites. As single crystals of g-alumina do not exist, we use some of a-alumina commercial wafers in order to mimic the g-alumina exposed surfaces.
Ammonium heptamolybdate complexes were deposited on the surface using conventional aqueous routes (“equilibrium” adsorption and impregnation). The samples were then calcined and sulphided. The samples were characterised (XPS, AFM) after each thermal treatment.
The sulphurisation degree was determined with sulphurisation temperature, and a correlation between the exposed sites and molybdenum sulphide is discussed. GI-EXAFS allowed us to show that the exposed surface induce in some case a certain orientation of MoS2slabs on the surface.
Hence it is possible to conclude that the control of the industrial support morphology constitutes a way to tune the genesis of the hydrotreating catalysts sulfide phase.