초록 ▼

According to one embodiment of the present invention, an enhanced NH3 adsorbing automotive exhaust composition including a catalyst composition suitable for use in a selective catalytic reduction (SCR) system and an acidified support composition for enhancing NH3 adsorption capacity of the automotiv

According to one embodiment of the present invention, an enhanced NH3 adsorbing automotive exhaust composition including a catalyst composition suitable for use in a selective catalytic reduction (SCR) system and an acidified support composition for enhancing NH3 adsorption capacity of the automotive exhaust composition is disclosed.

대표청구항 ▼

What is claimed: 1. An enhanced NH3 adsorbing automotive exhaust composition comprising: a catalyst composition suitable for use in a selective catalytic reduction (SCR) system wherein the catalyst composition comprises a combination of a cerium-containing oxide compound and non-cerium-containing m

What is claimed: 1. An enhanced NH3 adsorbing automotive exhaust composition comprising: a catalyst composition suitable for use in a selective catalytic reduction (SCR) system wherein the catalyst composition comprises a combination of a cerium-containing oxide compound and non-cerium-containing metal compound selected from the group consisting of alkali metal containing compounds, alkaline-earth metal containing compounds and combinations thereof; and an acidified support composition for enhancing NH3 adsorption capacity of the automotive exhaust composition. 2. The automotive exhaust composition of claim 1 wherein the acidified support composition comprises a support composition and a conjugate base oxide of an inorganic acid having a Ka in the range of 5.0×10−7 to 1.0. 3. The automotive exhaust composition of claim 2 wherein the Ka is in the range of 5.0×10−5 to 5.0×10−1. 4. The automotive exhaust catalyst composition of claim 2 wherein the conjugate base oxide is the conjugate base of an acid selected from the group consisting of H3PO4, H2TiO3, H2WO4, H2MoO3, HTa2O6, HNb2O6, H2CrO4 and combinations thereof. 5. The automotive exhaust catalyst composition of claim 2 wherein the support composition is selected from the group consisting of Al2O3, SiO2, TiO2, ZrO2, CeO2 and combinations thereof. 6. The automotive exhaust catalyst composition of claim 2 wherein the NH3 desorption per gram of acidified support composition is in the range of 3 to 25 ml upon substantially complete thermal release of NH3. 7. The automotive exhaust catalyst composition of claim 2 wherein the acidified support composition desorbs a substantial amount of NH3 in the range of temperatures from 150 to 350° C. during substantially complete thermal release of NH3 after saturation of the acidified support 5 composition with NH3. 8. A SCR system comprising: a substrate; and a catalyst composition coated upon the substrate comprising an acidified support composition for enhancing NH3 adsorption capacity of the SCR system, wherein the catalyst composition comprises a combination of a cerium-containing oxide compound and non-cerium-containing metal compound selected from the group consisting of alkali metal containing compounds, alkaline-earth metal containing compounds and combinations thereof. 9. The SCR system of claim 8 wherein the acidified support composition comprises a support composition and a conjugate base oxide of an inorganic acid having a Ka in the range of 5.0×10−7 to 1.0. 10. The SCR system of claim 9 wherein the Ka is in the range of 5.0×10−5 to 5.0×10−1. 11. The SCR system of claim 9 wherein the conjugate base oxide is the conjugate base of an acid selected from the group consisting of H3PO4, H2TiO3, H2WO4, H2MoO4, HTa2O6, HNb2O6, H2CrO4 and combinations thereof. 12. The SCR system of claim 9 wherein the support composition is selected from the group consisting of Al2O3, SiO2, TiO2, ZrO2, CeO2 and combinations thereof. 13. The SCR system of claim 9 wherein the NH3 desorption per gram of acidified support composition is in the range of 3 to 25 ml upon substantially complete thermal release of NH3 after saturation of the acidified support composition with NH3. 14. The SCR system of claim 9 wherein the acidified support composition desorbs a substantial amount of NH3 in the range of temperatures from 150 to 350° C. during substantially complete thermal release of NH3 after saturation of the acidified support composition with NH3.