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 invention is a mixed oxide oxygen storage material useful as a catalyst or catalyst washcoat. The mixed oxide is praseodymium oxide loaded onto a support of either cerium oxide or cerium-zirconium oxide. The praseodymium oxide is loaded on the support so that the resultant mixed oxide contains praseodymium and cerium in a molar ratio of 1:4 to 4:1. This mixed oxide may be loaded with a catalyst like palladium for use in automotive exhaust gas systems.

Abstract: The invention is a selective reduction catalyst useful for converting exhaust gases generated by a lean-burn engine where the atmosphere is oxidizing. The catalyst comprises zeolite containing two forms or rhodium, small metal particles and ion-exchanged into the zeolite, the latter being in significant excess. In addition, the catalyst contains a rare-earth metal having primarily a +3 or higher valence such as lanthanum in a significantly higher amount relative the total amount of rhodium.