Regeneration of aged commercial three-way catalytic converters

Abstract

The present work demonstrates for the first time that rejuvenation of the catalytic activity of full-scale aged commercial three-way catalytic (TWC) converters is feasible after treatment with weak oxalic acid solution (0.1 M). Up to 50% reduction in CO, 75% in NOx and 32% in HC emissions was attained under warm engine driving conditions following regeneration of three aged TWC converters with 42,500, 156,000 and 165,000 km mileage. Efforts to expand the durability of aged commercial TWC converters installed in gasoline-driven cars after applying specific treatments with weak oxalic acid-based solutions appear to be a very promising starting point in recovering to a very large degree their performance. © 2009 Springer Science+Business Media, LLC.