Exhaust purification system of internal combustion engine

Abstract

An exhaust purification system of an internal combustion engine including an ammonia oxidation catalyst device and an ammonia holding device arranged immediately upstream of the ammonia oxidation catalyst device is provided. The ammonia holding device has a solid acid, holds ammonia to restrain the ammonia from flowing into the ammonia oxidation catalyst device when a temperature of the ammonia oxidation catalyst device is within a N2O producing temperature range, and releases the held ammonia to make the ammonia flow into the ammonia oxidation catalyst device when the temperature of the ammonia oxidation catalyst device is out of the N2O producing temperature range.

Dependencies are inferred from the claim text.