Exhaust emission control apparatus for internal combustion engine

Abstract

One object of the present invention is to provide an exhaust emission control apparatus for an internal combustion engine that is capable of improving the NOx purification performance. An exhaust emission control apparatus being placed in an exhaust path of an internal combustion engine, comprising: an NOx retention material; ozone injection means for injecting ozone into an exhaust gas being positioned upstream from the NOx retention material; an HC adsorbent adsorbing HC contained in the exhaust gas; and a catalyst being placed in a region where desorbed NOx and desorbed HC contact each other. The HC adsorbent is prepared so as to desorb adsorbed HC at the same time as NOx being stored in the NOx retention material is desorbed.

Dependencies are inferred from the claim text.