Operando study of iridium acetylacetonate decomposition on amorphous silica-alumina for bifunctional catalyst preparation - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Physical Chemistry Chemical Physics Année : 2010

Operando study of iridium acetylacetonate decomposition on amorphous silica-alumina for bifunctional catalyst preparation

Résumé

The decomposition of iridium acetylacetonate Ir(acac)(3) impregnated on amorphous silica-alumina (ASA) has been investigated by combined thermogravimetry-differential thermal analysis-mass spectrometry (TG-DTA-MS) and by in situ X-ray diffraction (XRD). The resulting Ir/ASA hydrotreating catalysts have also been characterized by transmission electron microscopy (TEM). The effects of heating treatments under oxidative, reductive or inert gas flows are compared with each other and with similar experiments on ASA-supported acetylacetone (acacH). It is shown that Ir(acac)(3) undergoes exothermic combustion during calcination in air, leading to agglomerated IrO2 particles. Conversely, direct reduction involves hydrogenolysis of the acac followed by hydrogenation of the ligand residues to alkanes and water. These two processes are catalyzed by Ir clusters, the gradual growth of which is followed in situ by XRD. The resulting nanoparticles are highly and homogeneously dispersed.

Dates et versions

hal-00512072 , version 1 (27-08-2010)

Identifiants

Citer

S. Nassreddine, G. Bergeret, B. Jouguet, C. Geantet, L. Piccolo. Operando study of iridium acetylacetonate decomposition on amorphous silica-alumina for bifunctional catalyst preparation. Physical Chemistry Chemical Physics, 2010, 12 (28), pp.7812-7820. ⟨10.1039/b925062j⟩. ⟨hal-00512072⟩
72 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More