PURPOSE: To effectively decrease NOx in exhaust gas at a relatively low temp. as ≤500°C and to remove NOx at high removing rate by depositing no catalyst on a purifying member (filter) for exhaust gas.
CONSTITUTION: A porous ceramic layer having 2-400m2/g specific surface area is formed on the surface of a porous ceramic filter having 20-90 porosity to obtain a purying material for exhaust gas. This purifying member is installed in the middle of an exhaust gas flue. A liquid hydrocarbon is added to the exhaust gas in the upstream side of the purifying member. By maintaining temp. of the exhaust gas passing through the purifying member to 200-500°C, nitrogen oxides in the exhaust gas are reducd and removed by using a liquid hydrocarbon as a reducing agent.
MAKINO SEIJI
TAKAHASHI YOSHIKAZU
YOSHIDA KIYOHIDE
