| 摘要 |
An exhaust gas purification system for an internal combustion engine includes a first SCR catalyst (7a) and a second SCR catalyst (8), which carry out selective reduction of NOx in exhaust gas by using ammonia as a reducing agent, and which are arranged in an exhaust passage (3) of the internal combustion engine sequentially from an upstream side thereof, and further includes a control device (10) which carries out temperature rise control in which the temperature of the first SCR catalyst (7a) is controlled to be equal to or more than a predetermined temperature, wherein the control device (10) starts the temperature rise control at the time when an amount of ammonia adsorbed by the second SCR catalyst (8) is equal to or larger than a temperature rise start threshold value at which the temperature rise control is started. |
