EXHAUST GAS PURIFICATION SYSTEM, CATALYST, AND EXHAUST GAS PURIFICATION METHOD

摘要

An exhaust gas purification system which is capable of purifying exhaust gas without a noble metal being carried, and maintaining exhaust gas purification performance even at high temperatures; a catalyst; and an exhaust gas purification method are disclosed. A foamed metal catalyst which is made of a transition metal element excepting platinum group elements and is formed of a metal having a porosity of not less than 80%, and which reduces NOx by being brought into contact with an exhaust gas having a hydrogen concentration of not less than a predetermined concentration (e.g., 2%) and a temperature of not less than 230° C., is provided in an exhaust gas passage of an internal combustion engine that discharges the exhaust gas.

主权项

1. An exhaust gas purification system, comprising:
a heat engine that discharges exhaust gas; and a catalyst which is made of a transition metal element excepting platinum group elements, and is formed of a metal having a porosity of not less than 80%, the catalyst being provided in an exhaust gas passage of the heat engine to reduce NOx by being brought into contact with exhaust gas having a reducing gas concentration of not less than a predetermined concentration and a temperature of not less than 230° C.