Patent ID: 6962947
Filing Date: 2005-11-08
Classification: B01J,C07C,C10G,Y02P

Abstract:
1. A process for producing hydrocarbons, comprising the steps of: (a) carrying out a Fischer-Tropsch synthesis, comprising contacting a feed stream comprising hydrogen and carbon monoxide with a cobalt-containing catalyst in a reaction zone maintained at conversion-promoting conditions comprising a mean Fischer-Tropsch reaction pressure and a mean Fischer-Tropsch reaction temperature, said conversion-promoting conditions being effective to produce deactivated catalyst and an effluent stream comprising hydrocarbons, wherein the cobalt-containing catalyst has a pre-deactivation activity prior to the first time step (a) occurs, and wherein the activity of the catalyst drops to a deactivated level during step (a); (b) reducing the pressure to which at least a portion of the deactivated catalyst is subject to a regeneration pressure that is less than the mean Fischer-Tropsch reaction pressure by an amount between about 10 psig and about 300 psig; (c) carrying out a regeneration of said deactivated catalyst portion, comprising contacting the deactivated catalyst with a regeneration gas under regeneration-promoting conditions that include said regeneration pressure and a temperature that is between 0° C. and 150° C. higher than the mean temperature of the Fischer-Tropsch synthesis, for a period of time sufficient to reactivate the catalyst to a predetermined level of regenerated activity that equals or exceeds 50% of the pre-deactivation activity; (d) increasing the pressure to which the reactivated catalyst is subject to a desired Fischer-Tropsch reaction pressure after said sufficient period of time of regeneration; and (e) cycling through steps (a)-(d), depending on the status of the catalyst.