Patent ID: 8091343
Filing Date: 2012-01-10
Classification: F01N,Y02T

Abstract:
1. An exhaust gas purification apparatus for an internal combustion engine, applied to an exhaust purification system including a NOx catalyst adsorbing a reducer and selectively purifying NOx by the reducer, an oxidation catalyst disposed downstream of the NOx catalyst for oxidizing the reducer flowing out from the NOx catalyst, and an adding means for adding the reducer upstream of the NOx catalyst, the exhaust gas purification apparatus comprising: a heat value data computing means for computing a heat value data corresponding to a heat value in the oxidation catalyst; a reducer detecting means for detecting at least one of an existence or nonexistence of the reducer flowing out from the NOx catalyst and a flowing amount of the reducer; and an exhaust temperature detecting means for detecting a temperature of the exhaust gas flowing into the oxidation catalyst, wherein as the temperature of the exhaust gas is lower, a threshold of the heat value data for detecting an existence or nonexistence of the reducer is made smaller, or a flowing out amount of the reducer corresponding to the heat value data is made larger.