Ni (15 wt%)/Al2O3 catalysts prepared by decomposition of supported Ni(II)-ethylenediamine complexes in inert atmosphere, followed by post-treatment in hydrogen, are able to catalyze carbon monoxide hydrogenation at temperatures lower than for a catalyst prepared from nickel nitrate and containing a fraction of surface nickel aluminate. Unlike the latter, the catalyst prepared from Ni(II)-en complexes exhibits mostly surface metallic sites and is more stable under reaction despite the absence of nickel aluminate. Deactivation occurs during the reaction, probably by carbon deposition, but less strongly than for an ex-nickel nitrate catalyst. (C) 2009 Elsevier B.V. All rights reserved.