EXHAUST GAS PURIFYING DEVICE FOR INTERNAL COMBUSTION ENGINE

摘要

An exhaust purification system of an internal combustion engine is provided with an NO X storage reduction catalyst which is arranged in an engine exhaust passage and an SO X trap material which is arranged upstream of the NO X storage reduction catalyst and removes SO X which is contained in exhaust gas. A main flow path feeding fuel to combustion chambers of the engine body has a secondary flow path connected to it for bypassing the main flow path. In the secondary flow path, a removal device is arranged for removing the sulfur constituent which is contained in the fuel. Furthermore, an opening and closing device is provided which opens and closes the secondary flow path. When the SO X removal rate of the SO X trap material becomes a predetermined removal rate judgment value or less or the concentration of the SO X which flows into the SO X trap material becomes a predetermined concentration judgment value or more, at least part of the fuel flowing through the main flow path is made to flow into the secondary flow path and run through the removal device.