Durability of Palladium Only Three-way Automotive Emisson Control Catalysts 890794
The noble metal palladium (Pd) has the capability of simultaneously converting significant quantities of HC, CO and NOx in automotive exhaust. Primary interests in using palladium-containing TWC catalysts are overall noble metal cost reduction, reduction in rhodium usage and important performance advantages. Dynamometer aging experiments comparing palladium and platinum/rhodium catalysts were conducted under a variety of operating conditions. Vehicle evaluation of these aged catalysts under U.S. FTP-75, European ECE-15 and Japan 10-Mode conditions indicate that palladium-only TWC technology is viable for achieving high levels of three-way control. Vehicle aging studies (25K miles) were also conducted. They confirm the excellent durability results obtained from the dynamometer aging studies: the palladium-only TWC catalyst gave essentially equivalent U.S. FTP-75 and Japan 10-Mode performance to a high-tech platinum/rhodium catalyst.