Method for aftertreatment of exhaust gases of internal combustion engines and corresponding device

Abstract

A method and a device for the aftertreatment of exhaust gases of internal combustion engines, in particular for reducing the proportion of NO x in the exhaust gases, the NO x being reduced in the presence of O 2 using a reducing agent. The method and the device are characterized in that, prior to the reduction of the NO x , at least a proportion of the NO x or NO contained in the exhaust gas is converted into NO 2 .

1 - 7 . (canceled)  
     
     
         8 . A method for aftertreatment of an exhaust gas of an internal combustion engine, for reducing a proportion of NO x  in the exhaust gas, comprising: 
 introducing fuel as a reducing agent into an exhaust gas tract downstream from an oxidizing converter and upstream from an SCR catalytic converter;    converting at least a part of at least one of NO x  and NO contained in the exhaust gas into NO 2 , wherein the conversion involves catalytic oxidation in the oxidizing converter arranged upstream from the SCR catalytic converter; and    reducing, subsequent to the conversion step, NO x  in the presence Of O 2  by the SCR catalytic converter using the reducing agent.    
     
     
         9 . A device for aftertreatment of an exhaust gas of an internal combustion engine, for reducing a proportion of NO x  in the exhaust gas, comprising: 
 an exhaust gas tract including an SCR catalytic converter;    an oxidizing converter arranged upstream from the SCR catalytic converter; and    an introduction arrangement for introducing fuel as a reducing agent into the exhaust gas tract between the oxidizing converter and the SCR catalytic converter, downstream from the oxidizing converter and upstream from the SCR catalytic converter;    wherein at least a part of at least one of NO x  and NO contained in the exhaust gas is converted into NO 2 , the conversion involving catalytic oxidation in the oxidizing converter arranged upstream from the SCR catalytic converter, and wherein, subsequent to the conversion, NO x  is reduced in the presence of O 2  by the SCR catalytic converter using the reducing agent.