An exhaust emission control device for an internal combustion engine and a performance evaluation method for a NOx adsorbent

摘要

An exhaust emission control device for an internal combustion engine, the device comprising: a NOx adsorbent positioned in the exhaust path of the internal combustion engine; a NOx adsorption amount measuring means for measuring the amount of NOx adsorbed by the NOx adsorbent while the engine is in operation; a water adsorption amount measuring means for measuring the amount of water adsorbed by the NOx adsorbent while the engine is in operation; a reference value storage means for storing the reference value of the NOx adsorption amount with respect to the water adsorption amount; comparison means for comparing the measured NOx adsorption amount with the reference value of the NOx adsorption amount with respect to the measured water adsorption amount; and a signal outputting means for outputting a signal representing the result of the comparison.