Cobalt catalyst based on a medium containing a mixed oxide phase containing cobalt and / or nickel prepared by the use of oxalic acid or oxalate

The invention relates to a catalyst containing an active cobalt phase deposited on a support comprising alumina, silica or silica-alumina, said carrier containing a mixed oxide phase containing cobalt and / or nickel, said catalyst has been prepared by introducing at least one of oxalic acid or oxalate. The invention also relates to its use in the field of Fischer-Tropsch synthesis processes.