Device for purifying exhaust gas of engine

A device for purifying the exhaust gas of an engine having an exhaust passage, comprising:

• a sulphur containing components absorbent arranged in the exhaust passage, the sulphur containing components absorbent absorbing the sulphur containing components therein when the air-fuel ratio of the inflowing exhaust gas is lean, and releasing the absorbed sulphur containing components therefrom when the oxygen concentration in the inflowing exhaust gas becomes lower with the temperature of the sulphur containing components absorbent being higher than a sulphur containing components releasing temperature of the sulphur containing components absorbent;
• and
• releasing means for making the air-fuel ratio of the exhaust gas flowing to the sulphur containing components absorbent stoichiometric or rich temporarily, when the temperature of the sulphur containing components absorbent is higher than the sulphur containing components releasing temperature and when the flow rate of the exhaust gas flowing through the sulphur containing components absorbent is lower than a predetermined flow rate, to release the absorbed sulphur containing components from the sulphur containing components absorbent.