Patent ID: 6461992
Filing Date: 2002-10-08
Classification: B01D,B01J,C10G

Abstract:
A method for decreasing the environmental release of chloro-species from a moving bed process for regenerating spent catalyst particles wherein a flue stream comprising chloro-species is withdrawn from a regeneration zone containing chlorided catalyst particles, said process comprising:(a) passing a first portion of a recycle stream to a regeneration zone containing chlorided catalyst particles, at least partially regenerating at least a portion of said chlorided catalyst particles and removing at least a portion of the chloride from said chlorided catalyst particles at regeneration conditions to produce regenerated catalyst particles, and withdrawing from said regeneration zone a flue stream comprising chloro-species; (b) passing at least a portion of said flue stream to a sorption zone containing spent catalyst particles, sorbing at least a portion of the chloro-species in said at least a portion of said flue stream on said spent catalyst particles at sorption conditions to produce said chlorided catalyst particles having an increased content of chloride relative to said spent catalyst particles, said sorption conditions characterized by the substantial absence of carbon combustion, and withdrawing from said sorption zone said recycle stream having a reduced concentration of chloro-species relative to said at least a portion of said flue stream; (c) rejecting a second portion of said recycle stream from said process; and (d) at least periodically moving catalyst particles through said sorption zone and said regeneration zone by withdrawing regenerated catalyst particles from said regeneration zone, passing chlorided catalyst particles from said sorption zone to said regeneration zone, and adding spent catalyst particles to said sorption zone.