Process to determine the age-condition of a nitrogen oxide storage catalytic converter by comparison of de-toxified unit with original value

摘要

In a process to determine the age-condition (ATHERM) of an automotive nitrogen oxide (NOx) storage catalytic converter, a measurement is made of the reduction in storage capacity. The catalytic converter is de-toxified (sulfur) before determination of the age-condition. In a process to determine the age-condition (ATHERM) of an automotive nitrogen oxide (NOx) storage catalytic converter, a measurement is made of the reduction in storage capacity. The catalytic converter is de-toxified (sulfur) before determination of the age-condition. The catalytic converter is de-toxified if the decline in storage capacity (ATOTAL) exceeds the maximum permitted value (AMAX) using measurements obtained using sensors measuring the waste gas temperature and the oxygen and/or NOx content of the exhaust gases, and a further measurement (Ai) is then taken prior to a renewed determination of the age-condition after de-toxification and comparison with the original value (AMAX).