Chloride Management in Naphtha Reforming with Continuous Catalyst Regeneration: A Method to Reduce Chloride Emissions and Consumption

Naphtha reforming with continuous catalyst regeneration (CCR) is an important process for the production of high octane gasoline and aromatics.  Naphtha reforming catalysts are bi-functional catalysts that contain both acid and metal functions. The acid function is provided by chloride on the alumina base; as a result, chlorine containing compounds are present in the regenerator vent gas.  In order to comply with environmental regulations many refiners must treat the regenerator vent gas to remove chlorine containing compounds. One method for reducing chloride emissions is the use of a conventional vent gas caustic scrubbing system which consumes caustic and generates hazardous waste.  This contribution will compare a conventional vent gas scrubbing system to a system that captures chloride from the vent gas and recycles it back into the process, resulting in a 70% decrease in chloride consumption while simultaneously eliminating caustic usage.