IN SITU HYDROCARBON CONVERSION CATALYST REGENERATION AND SULFUR DECONTAMINATION OF VESSELS COMMUNICATING WITH CATALYST REACTOR

摘要

IN SITU HYDROCARBON CONVERSION CATALYST REGENERATIONAND SULFUR DECONTAMINATION OF VESSELSCOMMUNICATING WITH CATALYST REACTORAbstractA method is disclosed for regeneratingreforming catalysts containing a platinum groupcomponent and/or rhenium component in association witha halogen component on a porous inorganic oxide, suchas one containing alumina without significant dis-placement of the rhenium components by sulfur oxidesgenerated during the regeneration process. The methodis particularly characterized in that carbon isremoved from the catalyst by in situ oxidation attemperatures not in excess of about 750°F and withoutmodification of the catalytic reforming process flowcircuit, as by disconnecting or isolating the heatexchangers and furnace tubes.Sulfide scale is converted in a separateoxidation step to sulfur dioxide, SO2, withoutsubstantial oxidation to sulfur trioxide, SO3, bymaintaining the inner walls of the heat exchangers andfurnace tubes, where such iron sulfides are present,at a temperature not in excess of about 900°F and notless than about 750°F. and under regenerating condi-tions including a low oxygen, O2, concentration. Thesulfur dioxide then passes through the reforming cata-lyst without effectively displacing rhenium componentsfrom the carrier base. Further, by removal of thesesulfides, complete regeneration of the catalyst isfacilitated for subsequent redistribution of theplatinum component at temperatures in excess of 900°F,particularly when accompanied by halide addition.