Manufacture of higher ketones

Claim 1

In a process for the manufacture of a higher ketone by reacting an aldehyde of the formula ##STR3## where R 1 is unbranched or branched alkyl of 1 to 20 carbon atoms, aryl or cycloalkyl which are unsubstituted or substituted by lower alkyl groups, or aralkyl of 7 to 20 carbon atoms, and the said radicals may also carry one or more hydroxyl or alkoxy groups as inert substitutents, with a ketone of the formula CH.sub.3 --CO--R.sup.2 (II) where R 2 is unbranched or branched alkyl of 1 to 20 carbon atoms, aryl or cycloalkyl which are unsubstituted or substituted by lower alkyl groups, or aralkyl of 7 to 20 carbon atoms, and the said radicals may also carry one or more hydroxyl or alkoxy groups as inert substituents, in the presence of hydrogen and a catalyst system which possesses both condensing and hydrogenating properties, at an elevated temperature, the improvement which comprises: carrying out the reaction at from 80° to 280° C. in the presence of a catalyst system which comprises (i) an oxide or a salt of a rare earth metal or a mixture of two or more oxides and/or salts of rare earth metals and (ii) one or more metals of group VIII of the periodic table of the elements, the weight ratio of component (i) to component (ii) of the catalyst system being from 400:1 to 1:150.