A process for regenerating one or more deactivated cobalt comprising Fischer-Tropsch catalyst particle(s), comprising the steps of: (i) oxidizing the catalyst particle(s) at a temperature between 20 and 400° C.; (ii) treating the catalyst particle(s) for more than 5 minutes, (iii) drying the catalyst particle(s); and (iv) optionally reducing the catalyst particle(s) with hydrogen or a hydrogen comprising gas. This process may be preceded by a step in which Fischer-Tropsch product is removed from the catalyst particle(s). The treatment is performed using carbon dioxide and a liquid comprising ammonia.