Abstract: An improvement in the method of regenerating catalysts which have become inactive as a result of the accumulation of carbonaceous material on their surfaces during use by contacting them with a free oxygen-containing gas at an elevated temperature to burn the carbonaceous material from the catalyst is described. The improvement consists in wetting the catalyst with water and then contacting it with a free oxygen-containing gas at a temperature in the range about 300-600.degree. F. for a time sufficient to evaporate substantially all of the water from the catalyst surface before burning the carbonaceous material from the catalyst.

Abstract: A process for reactivating or regenerating catalysts which have become inactivated due to accumulation of carbon deposits or sulfur-containing carbon deposits on the catalyst surface during the course of use in catalytically refining various petroleum oils is described.