| abstract |
DISCHARGE PURIFICATION DEVICE AND INTERNAL COMBUSTION ENGINE DISCHARGE PURIFICATION METHOD. The present invention relates to a SOx trapping catalyst, (11) in which at least one of an alkali metal and an alkaline earth metal is charged diffusely and is disposed within an exhaust passage of an internal combustion engine. . Maintaining the temperature of the SOx trapping catalyst, (11) during engine operation at a temperature where a nitrate of at least one of the alkali metal and the alkaline earth metal becomes in the molten state, a motion action and of nitrate coagulation where the nitrate in the SOx trapping catalyst, (11) moves to and coagulates on the surface of the SOx trapping catalyst, (11) is promoted. Due to this nitrate coagulation and movement action, SOx is removed while restoring the SOx trapping rate. |