Patent ID: 8017544
Filing Date: 2011-09-13
Classification: B01J,C10G

Abstract:
1. A method for lowering nitrate content in a cobalt catalyst precursor comprising the steps of (i) impregnating a catalyst support with an aqueous solution of cobalt nitrate, (ii) calcining the impregnated support in air at a temperature in the range 130-500° C. to effect partial denitrification and form Co 3 O 4 and (iii) subsequently heating the calcined impregnated support comprising Co 3 O 4 to a temperature below 250° C. in the presence of a gas mixture comprising 0.1-10% hydrogen by volume in an inert gas to form a catalyst precursor, wherein the temperature and hydrogen content of the heating step are selected to reduce nitrate content and avoid causing any reduction of the cobalt to metallic form, and wherein the heating step (iii) is not performed in catalyst reduction equipment, a hydrogenation reactor, or a Fischer-Tropsch reactor.