Method for operation of a nox storage catalyst in internal combustion engines

Abstract

A method for the regeneration of an NOx store in the exhaust gas of internal combustion engines is presented. The NOx store takes up NOx from the exhaust gas when there is an oxygen excess therein and regenerates by outputting nitrogen when there is an oxygen deficiency in the exhaust gas. In the method, a reversal is made alternately between first phases having oxygen excess in the exhaust gas and second phases having oxygen deficiency. In the method, the oxygen deficiency in the exhaust gas is generated to regenerate the storage catalytic converter via a specific mass of fuel excess in the exhaust gas ahead of the NOx store. This mass is to be held constant.

1 . method for regenerating an nox store in the exhaust gas of internal combustion engines which takes up Nox from the exhaust gas for an oxygen excess therein and which regenerates by discharging nitrogen for an oxygen deficiency in the exhaust gas, in which method there is a reversal between first phases having oxygen excess and second phases having oxygen deficiency in the exhaust gas, characterized in that the oxygen deficiency in the exhaust gas is generated for regenerating the storage catalytic converter via a specific mass of fuel excess, which is to be held constant, in the exhaust gas forward of the Nox store: