| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method of cleaning a nitrogen oxide which can efficiently clean a nitrogen oxide of an exhaust containing a surplus oxygen equal to or beyond a stoichiometric ratio required for the oxidation of a component to be oxidized included in the exhaust, using hydrogen as a reducing agent, over a broad temperature window showing a coverage from low temperature zone to high temperature zone. <P>SOLUTION: This method of cleaning a nitrogen oxide is to clean the nitrogen oxide contained in the exhaust ejected from an internal combustion engine, using a nitrogen oxide cleaning catalyst with a first catalytic layer laminated on a second catalytic layer formed on a carrier. The nitrogen oxide cleaning catalyst is used which is of such a structure that the first catalytic layer has at least a function to remove carbon monoxide, and besides, the second catalytic layer has at least a function to remove the nitrogen oxide, using hydrogen as a reducing agent. Further, the nitrogen oxide cleaning catalyst is arranged in the exhaust containing the surplus oxygen equal to or beyond the stoichiometric ratio which is required for the oxidation of the component to be oxidized included in the exhaust, and hydrogen as the reducing agent and carbon monoxide, in order to allow the direction in which the catalytic layers are laminated to run orthogonally with the direction in which the exhaust flows. <P>COPYRIGHT: (C)2011,JPO&INPIT |
