초록 ▼

Disclosed are three-way catalysts that are able to simultaneously convert nitrogen oxides, carbon monoxide, and hydrocarbons in exhaust gas emissions into less toxic compounds. Also disclosed are three-way catalyst formulations comprising palladium (Pd)-containing oxygen storage materials. In some e

Disclosed are three-way catalysts that are able to simultaneously convert nitrogen oxides, carbon monoxide, and hydrocarbons in exhaust gas emissions into less toxic compounds. Also disclosed are three-way catalyst formulations comprising palladium (Pd)-containing oxygen storage materials. In some embodiments, the three-way catalyst formulations of the invention do not contain rhodium. Further disclosed are improved methods for making Pd-containing oxygen storage materials. The relates to methods of making and using three-way catalyst formulations of the invention.

대표청구항 ▼

1. An oxygen storage material (OSM) comprising a metal oxide doped with at least one transition metal, wherein said transition metal and OSM are present as a solid solution, wherein said OSM is doped with about 0.5-10% of said transition metal. 2. The OSM of claim 1, wherein said OSM is a Ce-based o

1. An oxygen storage material (OSM) comprising a metal oxide doped with at least one transition metal, wherein said transition metal and OSM are present as a solid solution, wherein said OSM is doped with about 0.5-10% of said transition metal. 2. The OSM of claim 1, wherein said OSM is a Ce-based oxygen storage material. 3. The OSM of claim 1, wherein said transition metal is selected from the group consisting of: Pd, Cu, Mn and Ni. 4. A washcoat or overcoat comprising the oxygen storage material (OSM) of claim 1. 5. A catalyst system comprising: a substrate and a washcoat, wherein said washcoat comprises an oxygen storage material (OSM), andwherein said OSM is an OSM of claim 1. 6. A catalyst system according to claim 5, which further includes an overcoat comprising a support oxide, an OSM and a metal catalyst. 7. A catalyst system according to claim 5, further comprising an overcoat, wherein said washcoat comprises a support oxide, an oxygen storage material (OSM) and a metal catalyst, andwherein said overcoat comprises an OSM. 8. The catalyst system of claim 5, wherein said washcoat comprises platinum group metal (PGM) catalyst. 9. The catalyst system of claim 5, wherein the overcoat further comprises Ca, Sr, Ba or La. 10. The catalyst system of claim 5, wherein the washcoat or overcoat comprises Pd at a concentration of about 5-100 g/ft3 and said catalyst system is substantially free of Rh. 11. An oxygen storage material (OSM) comprising a metal oxide doped with at least one transition metal, wherein said transition metal and OSM are present as a solid solution and wherein said OSM comprises one or more of: a. a SS Pd-IWCP OSM;b. 30% CeO2, 60% ZrO2, 5% Nd2O3 and 5% Y2O3 or (30% CeO2, 60% ZrO2, 5% Nd2O3 and 5% Pr6O11). 12. A catalyst system comprising: a substrate and a washcoat, wherein said washcoat comprises an oxygen storage material (OSM), andwherein said OSM is an OSM of claim 11. 13. The catalyst system of claim 12, wherein the washcoat or overcoat comprises Pd at a concentration of about 5-100 g/ft3 and said catalyst system is substantially free of Rh. 14. The catalyst system of claim 12, wherein the overcoat further comprises Ca, Sr, Ba or La. 15. A catalyst system comprising: a) an overcoat comprising an OSM and a Pd metal catalyst, wherein said OSM comprises 30% CeO2, 60% ZrO2, 5% Nd2O3, and 5% Pr6O11 (% by weight),and said overcoat comprises 5 g/ft3 of Pd; andb) a washcoat comprising an OSM and a Pd metal catalyst, wherein said OSM comprises 30% CeO2, 60% ZrO2, 5% Nd2O3 and 5% Y2O3 (% by weight),and said washcoat comprises 15 g/ft3 of Pd.