Abstract: This catalyst system simultaneously removes ammonia and enhances net NOx, conversion by placing an NH3—SCR catalyst formulation downstream of a lean NOx, trap. By doing so, the NH3—SCR catalyst adsorbs the ammonia from the upstream lean NOx, trap generated during the rich pulses. The stored ammonia then reacts with the NOx, emitted from the upstream lean NOx, trap—enhancing the net NOx, conversion rate significantly, while depleting the stored ammonia. By combining the lean NOx, trap with the NH3—SCR catalyst, the system allows for the reduction or elimination of NH3 and NOx, slip, reduction in NOx. spikes and thus an improved net NOx, conversion during lean and rich operation.

Abstract: This catalyst system simultaneously removes ammonia and enhances net NO, conversion by placing an NH3-SCR catalyst formulation downstream of a lean NOx trap. By doing so, the NH3-SCR catalyst adsorbs the ammonia from the upstream lean NOx trap generated during the rich pulses. The stored ammonia then reacts with the NOx emitted from the upstream lean NOx trap-enhancing the net NOx conversion rate significantly, while depleting the stored ammonia. By combining the lean NOx trap with the NH3-SCR catalyst, the system allows for the reduction or elimination of NH3 and NOx slip, reduction in NOx spikes and thus an improved net NOx conversion during lean and rich operation.

Abstract: This catalyst system simultaneously removes ammonia and enhances net NO, conversion by placing an NH3-SCR catalyst formulation downstream of a lean NOx trap. By doing so, the NH3-SCR catalyst adsorbs the ammonia from the upstream lean NOx trap generated during the rich pulses. The stored ammonia then reacts with the NOx emitted from the upstream lean NOx trap—enhancing the net NOx conversion rate significantly, while depleting the stored ammonia. By combining the lean NOx trap with the NH3-SCR catalyst, the system allows for the reduction or elimination of NH3 and NOx slip, reduction in NO. spikes and thus an improved net NOx conversion during lean and rich operation.

Abstract: A catalyst system for use with an internal combustion engine to provide emissions reductions under lean and stoichiometric operating conditions. The catalyst system comprises a first catalyst comprised of a newly developed Perovskite-based formulation having an ABO3 crystal structure designed to bring the precious metal and NOx trapping elements close together. The first catalyst acts primarily to maximize the reduction of emissions under lean operating conditions. The catalyst system also comprises a second catalyst comprised of precious metals which acts primarily to maximize the reduction of emissions under stoichiometric conditions.

Abstract: The present invention involves an exhaust gas catalyst and method of manufacturing same. The invention provides for a cost-effective material which lowers the cold-start emissions from the exhaust of vehicles. The invention is a passive system which accelerates the light-off temperature of catalyst in a cost-effective fashion. The invention includes a method of manufacturing an exhaust gas catalyst capable of lowering cold-start emissions including the steps of providing an oxide mixture having praseodymium and cerium, doping about 0-10% weight zirconium and about 0-10% weight yttrium to the oxide mixture, adding about 0-2% weight metal including palladium, platinum, or rhodium to the oxide mixture, mixing gamma aluminum to the oxide mixture for washcoating and washcoating the oxide mixture onto a monolithic substrate.