Cobalt catalysts

A process for preparing a cobalt catalyst precursor, which process includes

• in a support impregnation stage, impregnating a particulate porous catalyst support with a cobalt salt, and partially drying the impregnated support, with the resultant partially dried impregnated support containing residual moisture;
• and
• in a calcination stage, calcining the partially dried impregnated support to obtain the cobalt catalyst precursor, with the calcination being effected in air at a temperature between 95° C. and 400° C, and by using an air space velocity and a support heating rate such that all reducible cobalt is present in the support of the precursor as a supported cobalt oxide of formula-unit CoOaHb, where a≧1.7 and b>0.

A process for preparing a cobalt catalyst precursor, which process includes

• in a support impregnation stage, impregnating a particulate porous catalyst support with a cobalt salt, and partially drying the impregnated support, with the resultant partially dried impregnated support containing residual moisture;
• and
• in a calcination stage, calcining the partially dried impregnated support by passing air over and around the partially dried impregnated support, and heating the impregnated support to a temperature between 95° C. and 400° C. to obtain the cobalt catalyst precursor, wherein the heating rate of the impregnated support and the space velocity of the air are controlled such that the residual moisture in the support is first driven off, whereafter decomposition of the cobalt salt into decomposition products comprising oxide(s) and any water of hydration, is effected, and wherein all reducible cobalt then is present in the support of the precursor as a supported cobalt oxide of formula-unit CoOaHb, where a≧1.7 and b>0.