US 7,520,126 B2
Exhaust purification method and exhaust purification apparatus of internal combustion engine
Shinicihi Takeshima, Numazu (Japan); Toshiaki Tanaka, Numazu (Japan); and Tetsuya Yamashita, Gotenba (Japan)
Assigned to Toyota Jidosha Kabushiki Kaisha, Toyota (Japan)
Appl. No. 10/544,795
PCT Filed Feb. 12, 2004, PCT No. PCT/JP2004/001493
§ 371(c)(1), (2), (4) Date Sep. 14, 2005,
PCT Pub. No. WO2004/074650, PCT Pub. Date Feb. 09, 2004.
Claims priority of application No. 2003-041031 (JP), filed on Feb. 19, 2003.
Prior Publication US 2006/0137328 A1, Jun. 29, 2006
Int. Cl. F01N 3/10 (2006.01)
U.S. Cl. 60—301  [60/274; 60/285; 60/295; 60/297; 60/303] 23 Claims
OG exemplary drawing
 
1. An exhaust purification method of an internal combustion engine wherein combustion gas or burned gas in an engine combustion chamber or an exhaust gas exhausted from the engine combustion chamber is brought into contact with a NOx storing and decomposing catalyst, nitrogen oxide contained in these gases is adsorbed at the NOx storing and decomposing catalyst and disassociated to nitrogen and oxygen when burning fuel under a lean air-fuel ratio, the disassociated oxygen is held on the NOx storing and decomposing catalyst at this time, the disassociated nitrogen is separated from the NOx storing and decomposing catalyst, an energy necessary for purging part of the oxygen held on the NOx storing and decomposing catalyst from the NOx storing and decomposing catalyst is imparted to the NOx storing and decomposing catalyst to purge part of the oxygen held on the NOx storing and decomposing catalyst from the NOx storing and decomposing catalyst, and this purging action induces the remaining oxygen held on the NOx storing and decomposing catalyst to be purged from the NOx storing and decomposing catalyst,
wherein oxygen defects formed in the carrier of the NOx storing and decomposing catalyst are given electrons. ultrastrong basic points are formed, and nitrogen monoxide contained in the gas is adsorbed at the ultrastrong basic points and disassociated to nitrogen and oxygen.