Process for the preparation of surface impregnated dispersed cobalt metal catalysts

In a process for the production of catalysts wherein a catalytically effective amount of cobalt is impregnated and dispersed on the outer surface of a particulate porous inorganic oxide support to form a catalyst useful for the conversion of synthesis gas to hydro-carbons, and the support particles are contacted with a spray containing a decomposable compound of cobalt,

• the improvement comprising
• maintaining a bed of the support particles in a fluidized state at temperature ranging from about 50.degree. C. to about 100.degree. C. by contact with a gas at temperature ranging from about 50.degree. C. to about 100.degree. C.,
• spraying the bed of the heated support particles with a liquid in which a cobalt compound is dispersed at flow rate sufficient to provide a ratio between the flow rate of the liquid:
• flow rate of the fluidizing gas below about 0.6 grams liquid/ft.sup.3 of fluidizing gas to form on the particles a surface layer of cobalt compound in average thickness ranging from about 20 microns to about 250 microns, with the loading of cobalt compound ranging from about 0.01 g/cc to about 0.15 g/cc, calculated as metallic cobalt per packed bulk volume of catalyst.