Size-Dependent Activity and Selectivity of Fe/MCF-17 in the Catalytic Hydrogenation of Carbon Monoxide Using Fe(0) Nanoparticles as Precursors

Viacheslav Iablokov (1) , Yizhi Xiang (2, 1) , Anca Meffre (3) , Pier-Francesco Fazzini (3) , Bruno Chaudret (4) , Norbert Kruse (1, 2)

1 CPM-ULB - Chemical Physics of Materials
2 WSU - Washington State University
3 LPCNO - Laboratoire de physique et chimie des nano-objets
4 LCC - Laboratoire de chimie de coordination

Monodisperse Fe(0) nanoparticles with diameters between 1.8 and 9.0 nm were prepared from organometallic {Fe[N(SiMe3)2]2}2 and intercalated into mesoporous MCF-17 silica. We observed high turnover frequencies of the catalytic CO hydrogenation; they increased with Fe particle size. Methane and short-chain olefin selectivities were highest for small particles, while the opposite trend applied to long-chain terminal olefins and oxygenates. The Anderson–Schulz–Flory chain lengthening probabilities were found to increase with Fe particle size for both paraffins and terminal olefins. Reaction-induced sintering of the metal particles was limited and could be explained by the transformation of Fe(0) precursors into (mainly) Fe-carbides. The results cast new light on the structure sensitivity of the catalytic CO hydrogenation.

Mots clés: Fe(0); Fe/MFC-17; Particle size effect; Fischer-Tropsch; CO hydrogenation

Domaines: Chimie-Physique [physics.chem-ph]

Viacheslav Iablokov, Yizhi Xiang, Anca Meffre, Pier-Francesco Fazzini, Bruno Chaudret, et al.. Size-Dependent Activity and Selectivity of Fe/MCF-17 in the Catalytic Hydrogenation of Carbon Monoxide Using Fe(0) Nanoparticles as Precursors. ACS Catalysis, 2016, 6 (4), pp.2496-2500. ⟨hal-01983179⟩