Abstract: The present invention provides a regenerable catalyst composition suitable for entrapping SOx. The composition of the invention comprises a copper oxide having the formula (Cu/(A oxide) where A oxide is SiO2, Zr—SiO2, Al2O3, TiO2—Al2O3, ZrO2 and In2O3 or mixtures thereof. Copper loading may vary from about 10 to 60 mol % and is preferably about 25 mol %. The catalyst composition adsorbs SOx as metal sulfate under lean conditions and desorbs accumulated SOx as SO2 under rich conditions. Such reversible SOx trap are able to operate under conventional NOx trap operating conditions to prevent sulfur poisoning of the NOx trap. Furthermore, these traps may be regenerated under rich conditions at 300-450° C. In another embodiment of the present invention, an irreversible SOx trap capable of collecting SOx under lean conditions is provided. The traps of this embodiment include praseodymia, zirconia-praseodymia and mixed manganese-yttria and mixtures thereof.

Abstract: The present invention provides a regenerable catalyst composition suitable for entrapping SOx. The composition of the invention comprises a copper oxide having the formula (Cu/(A oxide) where A oxide is SiO2, Zr—SiO2, A12O3, TiO2—Al2O3, ZrO2 and In2O3 or mixtures thereof. Copper loading may vary from about 10 to 60 mol % and is preferably about 25 mol %. The catalyst composition adsorbs SOx as metal sulfate under lean conditions and desorbs accumulated SOx as SO2 under rich conditions. Such reversible SOx trap are able to operate under conventional NOx trap operating conditions to prevent sulfur poisoning of the NOx trap. Furthermore, these traps may be regenerated under rich conditions at 300-450° C. In another embodiment of the present invention, an irreversible SOx trap capable of collecting SOx under lean conditions is provided. The traps of this embodiment include praseodymia, zirconia-praseodymia and mixed manganese-yttria and mixtures thereof.

Abstract: The present invention discloses a method for reducing NOx in exhaust gases of an internal combustion engine. The purpose of this invention is to convert engine out NOx (approximately 90% NO in diesel exhaust) into roughly a 50:50 mixture of NO and NO2, while simultaneously oxidizing engine-out hydrocarbons which interfere with the reduction of NOx by urea or ammonia. The present invention demonstrates that a 50:50 blend of NO and NO2 is reduced more rapidly and with higher efficiency than a gas stream which is predominantly NO. In addition, catalyst in an engine exhaust that is a 50:50 mixture of NO and NO2 is far more resistant to hydrothermal deterioration than using NO alone. In another embodiment of the present invention, a vehicle exhaust system utilizing the method of the present invention is provided.

Abstract: A dual-phase zeolite having a transition metal-containing zeolite phase and a transition metal-containing oxide phase. The catalytic material may be an intimate mixture of a phase-layered structure of a first phase constituted preferably of a copper-containing high silica zeolite and a second phase constituted of copper-containing zirconia.Methods are also disclosed for making a single-stage catalyst for removing NO.sub.x and HC at high efficiency in an oxygen-rich automotive exhaust gas, and for treating the exhaust gas with the dual-phase catalyst above.

Abstract: A dual-phase zeolite having a transition metal-containing zeolite phase and a transition metal-containing oxide phase. The catalytic material may be an intimate mixture of a phase-layered structure of a first phase constituted preferably of a copper-containing high silica zeolite and a second phase constituted of copper-containing zirconia.Methods are also disclosed for making a single-stage catalyst for removing NO.sub.x and HC at high efficiency in an oxygen-rich automotive exhaust gas, and for treating the exhaust gas with the dual-phase catalyst above.

Abstract: A dual-phase zeolite having a transition metal-containing zeolite phase and a transition metal-containing oxide phase. The catalytic material may be an intimate mixture of a phase-layered structure of a first phase constituted preferably of a copper-containing high silica zeolite and a second phase constituted of copper-containing zirconia.Methods are also disclosed for making a single-stage catalyst for removing NO.sub.x and HC at high efficiency in an oxygen-rich automotive exhaust gas, and for treating the exhaust gas with the dual-phase catalyst above.