Process for preparing cobalt based catalysts for fischer-tropsch synthesis

A method for preparing a cobalt-based catalyst for Fischer-Tropsch synthesis, comprising:

• preparing an alumina sol by adding an organic binder and a dispersant to an aluminum precursor solution and stirring at 50-90° C. and at pH 3-6 and then converting the alumina sol to an alumina gel by heating at 50-90° C.;
• preparing an η-alumina support by drying the alumina gel at 150-230° C., forming into spheres and sintering under nitrogen flow;
• preparing Co/η-alumina by repeating a procedure of impregnating the η-alumina support in a cobalt precursor solution and drying at 50-100° C. 10-20 times to support cobalt on the η-alumina support and sintering same under air flow;
• and
• preparing a cobalt-based catalyst represented by Chemical Formula 1 by impregnating the Co/η-alumina in an iridium precursor solution to support iridium on the Co/η-alumina and sintering same under air flow:
• aIr—bCo/η-Al2O3 [Chemical Formula 1]
• wherein a and b are supporting amounts of iridium (Ir) and cobalt (Co) based on the weight of the η-alumina support, with a being 0.01-5 wt % and b being 0.1-30 wt %.