Catalyst Regeneration, Metal Catalysts

Abstract

AbstractThe regeneration of deactivated heterogeneous noble metal catalysts, such as promoted platinum‐alumina reforming catalyst, can be successfully achieved by the removal of carbonaceous deposits from the catalyst surface using a carefully controlled combustion procedure followed by platinum redispersion and rechloriding of the catalyst support. Three regeneration techniques are in common commercial practice for noble metal catalysts. The continuous catalyst regeneration system used in the CCR Platforming process continuously circulates spherical catalyst between the regeneration vessel and the process reactors. The regeneration methods used for fixed catalyst‐bed reforming processes are also discussed. Regeneration of non‐noble or base metal catalysts such as those used in hydrocracking processes can also successfully restore catalyst performance to near that of fresh catalyst. Catalysts containing base metal hydrogenation components, such as nickel, cobalt, molybdenum, and tungsten, and an acidic support, such as alumina, silica‐alumina, or zeolites, are used in a variety of refining processes. If catalyst deactivation in this service is a result of carbonaceous deposits, the catalytic performance can be substantially improved by a regenerative oxidation treatment to remove this deposit. Theex situregeneration is performed in moving‐bed belt calciners or conical‐shaped rotating drum calciners.