A process for operating a palladium oxide-containing catalytic combustor is useful, e.g., for powering a gas turbine. The palladium oxide is supported on a metal oxide such as alumina, lanthanide metal oxide-modified alumina, ceria, titania or tantalum oxide. The method involves maintaining control of the temperature within the combustor in such a manner as to insure the presence of palladium oxide. By maintaining the temperature below the decomposition onset temperature of palladium oxide (which is catalytically active for catalytic combustion) into metallic palladium (which is catalytically inactive) deactivation of the catalyst is avoided and high catalytic activity is retained. Regeneration of catalyst following inactivation resulting from an over-temperature is accomplished by using a heat soak in a regeneration temperature range which varies depending on the particular metal oxide used to support the palladium oxide.