Exhaust purification device of internal combustion engine

An exhaust purification device of an internal combustion engine, comprising:

• an NOx storage catalyst disposed in an engine exhaust passage, the NOx storage catalyst storing NOx contained in an exhaust gas when an air-fuel ratio of an inflowing exhaust gas is lean and releasing stored NOx when the air-fuel ratio of the inflowing exhaust gas becomes the stoichiometric air-fuel ratio or rich;
• an NOx adsorption catalyst disposed upstream of the NOx storage catalyst in the engine exhaust passage that adsorbs NOx contained in the exhaust gas when the NOx adsorption catalyst is at a low temperature and that desorbs adsorbed NOx when the temperature of the NOx adsorption catalyst rises;
• and
• an electronic control unit (ECU) programmed to execute control of the exhaust purification device such that when the NOx storage catalyst is active and able to store NOx, the ECU executes programmed instructions to control a temperature of the NOx adsorption catalyst such that the temperature of the NOx adsorption catalyst is forcibly made to rise to a target temperature at which an amount of NOx which the NOx storage catalyst can store is desorbed, and the NOx desorbed from the NOx adsorption catalyst is made to be stored in the NOx storage catalyst.