Modelisation of the interactions of vanadyl porphyrins with hydroprocessing catalysts

Abstract This paper first compares the X-ray Fluorescence excitation spectra of several vanadyl porphyrins which differ by the nature of appended functional groups. The aim of these investigations was to check whether structural distortions associated with chemical modifications of the porphyrin ligand can be detected from the EXAFS spectra and modelised. Good quality spectra were next accumulated on samples of [OEP:V = O] adsorbed on an industrial Ni-Mo-Al 2 O 3 catalyst and on the bare support used in the preparation of this catalyst. Finally, we succeeded in synthetizing and studying by X.A.S. the first stable venadyl chlorin [TPyr-Chl:V=O].