Patent ID: 11002204

Abstract:
An exhaust purification system of an internal combustion engine comprises an HC adsorbent 20 arranged adsorbing HC in exhaust gas, an NOx adsorbent 20 adsorbing NOx in exhaust gas, a catalyst 24 removing HC and NOx at a predetermined air-fuel ratio, an air-fuel ratio control part 31 configured to control an air-fuel ratio of exhaust gas, and an HC concentration calculating part 32 configured to calculate a concentration of HC desorbed from the HC adsorbent. A peak of a desorption temperature of HC at the HC adsorbent and a peak of a desorption temperature of NOx at the NOx adsorbent are substantially the same. The air-fuel ratio control part is configured to control an air-fuel ratio of inflowing exhaust gas flowing into the catalyst to the predetermined air-fuel ratio based on the concentration of HC calculated by the HC concentration calculating part when HC is desorbed from the HC adsorbent.