Primary alcohols were transfered into the corresponding aldehydes by catalytic oxidation with heterogeneous ruthenium catalysts. Ru(III) and Ru(O) species were deposited on titania and zirconia supports by wet chemical and plasmachemical methods. The dispersion of the catalytically active centres influenced significantly the catalytic activity. The doping of the Ru catalysts with promoter metals such as Fe, Cu, Mn, Co, and Mo was also investigated. The Ru/Co and Ru/Mn catalysts 13 and 14 led to an increase in the conversion of benzyl alcohol and I-octanol in the oxidation with molecular oxygen. With bleach and TBHP as oxidants the promoter metals had a detrimental effect. Wet chemically prepared Ru/TiO2(P25) catalysts showed the highest aldehyde selectivities in these oxidations. (c) 2005 Elsevier B.V. All rights reserved.