Scr exhaust-gas aftertreatment device and motor vehicle with such an scr exhaust-gas aftertreatment device

Abstract

An exhaust-gas aftertreatment device for an aftertreatment of the exhaust-gas of an internal combustion engine includes an SCR catalytic converter and an SCR particulate filter downstream of the SCR catalytic converter. The SCR catalytic converter has an SCR catalytic coating for a selective reduction of nitrogen oxides in the presence of a reducing agent added to the exhaust-gas in a metered manner. The SCR catalytic converter has a flow-through substrate. The SCR catalytic coating of the SCR catalytic converter is disposed on the flow-through substrate. The SCR particulate filter has an SCR catalytic coating for a selective reduction of nitrogen oxides in the presence of the reducing agent added to the exhaust-gas in a metered manner. The SCR particulate filter has a particulate filter substrate. The SCR catalytic coating of the SCR particulate filter is disposed on the particulate filter substrate.

What is claimed is: 
     
         1 . An exhaust-gas aftertreatment device for an aftertreatment of an exhaust-gas of an internal combustion engine, comprising:
 an SCR catalytic converter having an SCR catalytic coating for a selective reduction of nitrogen oxides in a presence of a reducing agent added to the exhaust-gas in a metered manner, said SCR catalytic converter having a flow-through substrate, said SCR catalytic coating of said SCR catalytic converter being disposed on said flow-through substrate; and   an SCR particulate filter downstream of said SCR catalytic converter, said SCR particulate filter having an SCR catalytic coating for a selective reduction of nitrogen oxides in a presence of the reducing agent added to the exhaust-gas in a metered manner, said SCR particulate filter having a particulate filter substrate, said SCR catalytic coating of said SCR particulate filter being disposed on said particulate filter substrate.   
     
     
         2 . The exhaust-gas aftertreatment device according to  claim 1 , wherein said SCR catalytic converter and said SCR particulate filter each have a respective volume, said volume of said SCR catalytic converter is smaller than said volume of said SCR particulate filter. 
     
     
         3 . The exhaust-gas aftertreatment device according to  claim 2 , wherein said volume of said SCR catalytic converter is at most 75% of said volume of said SCR particulate filter. 
     
     
         4 . The exhaust-gas aftertreatment device according to  claim 2 , wherein said volume of said SCR catalytic converter is at most 60% of said volume of said SCR particulate filter. 
     
     
         5 . The exhaust-gas aftertreatment device according to  claim 1 , wherein:
 said flow-through substrate and said particulate filter substrate each have a respective substrate volume; and   said SCR catalytic converter and said SCR particulate filter each have a respective amount of said SCR catalytic coating in relation to the respective substrate volume, said amount of said SCR catalytic coating in relation to said substrate volume of said flow-through substrate of said SCR catalytic converter is at least equal to or larger than said amount of said SCR catalytic coating in relation to said substrate volume of said particulate filter substrate of said SCR particulate filter.   
     
     
         6 . The exhaust-gas aftertreatment device according to  claim 5 , wherein said amount of said SCR catalytic coating in relation to said substrate volume of said flow-through substrate of said SCR catalytic converter is larger by a factor of at least 1.2 than said amount of said SCR catalytic coating in relation to said substrate volume of said particulate filter substrate of said SCR particulate filter. 
     
     
         7 . The exhaust-gas aftertreatment device according to  claim 5 , wherein said amount of said SCR catalytic coating in relation to said substrate volume of said flow-through substrate of said SCR catalytic converter is larger by a factor of at least 1.5 than said amount of said SCR catalytic coating in relation to said substrate volume of said particulate filter substrate of said SCR particulate filter. 
     
     
         8 . The exhaust-gas aftertreatment device according to  claim 1 , wherein said flow-through substrate of said SCR catalytic converter and said particulate filter substrate of said SCR particulate filter each have a respective cell count, said cell count of said flow-through substrate is greater than said cell count of said particulate filter substrate. 
     
     
         9 . The exhaust-gas aftertreatment device according to  claim 8 , wherein said cell count of said flow-through substrate is greater by a factor of at least 1.1 than said cell count of said particulate filter substrate. 
     
     
         10 . The exhaust-gas aftertreatment device according to  claim 8 , wherein said cell count of said flow-through substrate is greater by a factor of at least 1.2 than said cell count of said particulate filter substrate. 
     
     
         11 . The exhaust-gas aftertreatment device according to  claim 1 , including a common housing, said SCR catalytic converter and said SCR particulate filter being disposed in said common housing. 
     
     
         12 . The exhaust-gas aftertreatment device according to  claim 1 , including a reducing agent metering device, said reducing agent metering device being configured to add one of the reducing agent and a precursor compound of the reducing agent in a metered manner to the exhaust-gas upstream of said SCR catalytic converter. 
     
     
         13 . The exhaust-gas aftertreatment device according to  claim 1 , including an oxidation catalytic converter. 
     
     
         14 . The exhaust-gas aftertreatment device according to  claim 13 , wherein said oxidation catalytic converter is disposed upstream of said SCR catalytic converter. 
     
     
         15 . In combination with an internal combustion engine, an exhaust-gas aftertreatment device for an aftertreatment of an exhaust-gas of the internal combustion engine, comprising:
 an SCR catalytic converter having an SCR catalytic coating for a selective reduction of nitrogen oxides in a presence of a reducing agent added to the exhaust-gas in a metered manner, said SCR catalytic converter having a flow-through substrate, said SCR catalytic coating of said SCR catalytic converter being disposed on said flow-through substrate;   an SCR particulate filter downstream of said SCR catalytic converter, said SCR particulate filter having an SCR catalytic coating for a selective reduction of nitrogen oxides in a presence of the reducing agent added to the exhaust-gas in a metered manner, said SCR particulate filter having a particulate filter substrate, said SCR catalytic coating of said SCR particulate filter being disposed on said particulate filter substrate; and   at least said SCR catalytic converter being disposed in a position close to the internal combustion engine.   
     
     
         16 . The exhaust-gas aftertreatment device according to  claim 15 , wherein the internal combustion engine has an exhaust-gas manifold with a cylinder-side inlet opening, said SCR catalytic converter has an inflow face side, a distance between the cylinder-side inlet opening of the exhaust-gas manifold and said inflow face side of said SCR catalytic converter is at most 100 cm. 
     
     
         17 . The exhaust-gas aftertreatment device according to  claim 16 , wherein the distance between the cylinder-side inlet opening of the exhaust-gas manifold and said inflow face side of said SCR catalytic converter is at most 80 cm. 
     
     
         18 . A motor vehicle comprising:
 an internal combustion engine;   an exhaust-gas aftertreatment device for an aftertreatment of an exhaust-gas of said internal combustion engine, said exhaust-gas aftertreatment device including an SCR catalytic converter and an SCR particulate filter;   said SCR catalytic converter having an SCR catalytic coating for a selective reduction of nitrogen oxides in a presence of a reducing agent added to the exhaust-gas in a metered manner, said SCR catalytic converter having a flow-through substrate, said SCR catalytic coating of said SCR catalytic converter being disposed on said flow-through substrate; and   said SCR particulate filter being disposed downstream of said SCR catalytic converter, said SCR particulate filter having an SCR catalytic coating for a selective reduction of nitrogen oxides in a presence of the reducing agent added to the exhaust-gas in a metered manner, said SCR particulate filter having a particulate filter substrate, said SCR catalytic coating of said SCR particulate filter being disposed on said particulate filter substrate.