Patent ID: 7374728

Claim:
An exhaust gas purification system that is equipped, from an upstream side toward downstream side through which an exhaust gas flows, with a plasma reactor and a NO x selective reduction catalyst unit having a NO x selective reduction catalyst layer acting on said exhaust gas, and which system provides a reducing agent adding means adding a reducing agent to said exhaust gas at an upstream side of said plasma reactor, wherein said NO x selective reduction catalyst layer comprises nickel and a NO x selective reduction catalyst; wherein said NO x selective reduction catalyst comprises a first purification unit where an exhaust gas is introduced via said plasma reactor, and a second purification unit where an exhaust gas is introduced via said first purification unit; and wherein said first purification unit comprises an Ag/Al 2 O 3 catalyst where Ag is supported by alumina, and said second purification unit comprises an Ag/zeolite catalyst where Ag is supported by zeolite.