TY - JOUR
T1 - Catalysis by supported clusters
T2 - Chemisorption, decomposition and catalytic properties in fischer-tropsch synthesis of Fe3(CO)12, [H Fe3(CO)11]- (and Fe(CO)5) supported on highly divided oxides
AU - Hugues, F.
AU - Bussiere, P.
AU - Basset, Jean-Marie Maurice
AU - Commereuc, D.
AU - Chauvin, Y.
AU - Bonneviot, L.
AU - Olivier, D.
PY - 1981/1/1
Y1 - 1981/1/1
N2 - Fe(CO)5, Fe3(CO)12 and [H Fe3(CO)11]− supported on Al2O3 or MgO exhibit after decomposition under CO + H2 a very high selectivity for low molecular weight olefins. Characterisation of the supported complexes before and after decomposition has been carried out using Ferromagnetic Resonance, Mössbauer Spectroscopy, Electron Microscopy and analysis of the gas phase. The behaviour of the precursor carbonyl depends on the water content of the support before impregnation: with dehydroxylated alumina and magnesia, thermal decomposition (T < 200°C) into superparamagnetic very small metal particles (q < 15 Å) occurs. Above 200°C, sintering to particles of higher sizes occurs to a certain extent. With hydroxylated alumina and magnesia, thermal decomposition leads to a mixture of superparamagnetic metallic particles and iron oxides. The oxidation of zerovalent icon is due to surface protons with evolution of hydrogen. The resulting high selectivities for low molecular weight olefins (ethylene, propylene) would result from the low particle sizes of metallic iron generated from zerovalent cluster carbonyls.
AB - Fe(CO)5, Fe3(CO)12 and [H Fe3(CO)11]− supported on Al2O3 or MgO exhibit after decomposition under CO + H2 a very high selectivity for low molecular weight olefins. Characterisation of the supported complexes before and after decomposition has been carried out using Ferromagnetic Resonance, Mössbauer Spectroscopy, Electron Microscopy and analysis of the gas phase. The behaviour of the precursor carbonyl depends on the water content of the support before impregnation: with dehydroxylated alumina and magnesia, thermal decomposition (T < 200°C) into superparamagnetic very small metal particles (q < 15 Å) occurs. Above 200°C, sintering to particles of higher sizes occurs to a certain extent. With hydroxylated alumina and magnesia, thermal decomposition leads to a mixture of superparamagnetic metallic particles and iron oxides. The oxidation of zerovalent icon is due to surface protons with evolution of hydrogen. The resulting high selectivities for low molecular weight olefins (ethylene, propylene) would result from the low particle sizes of metallic iron generated from zerovalent cluster carbonyls.
UR - http://www.scopus.com/inward/record.url?scp=20344394327&partnerID=8YFLogxK
U2 - 10.1016/S0167-2991(09)60288-3
DO - 10.1016/S0167-2991(09)60288-3
M3 - Article
AN - SCOPUS:20344394327
VL - 7
SP - 418
EP - 431
JO - Studies in Surface Science and Catalysis
JF - Studies in Surface Science and Catalysis
SN - 0167-2991
ER -