CATALYST FOR PURIFYING EXHAUST GAS

摘要

PURPOSE:To provide a catalyst for purifying exhaust gas capable of purifying nitrogen oxide to a harmless gas at high efficiency even if the oxygen conc. in the exhaust gas is high. CONSTITUTION:The catalyst is composed of a carrier carrying copper component and phosphorus component (phosphor, phosphorus compound) containing a pentasyl type (constitution unit is oxygen 5-members ring) crystalline aluminosilicate. The carrying quantity of phosphorus component is 0.01-6.0wt.% in terms of P2O5 and <=0.7 in the ratio of phosphorus to copper (P/Cu mol ratio). The exhaust gas is purified by using the catalyst in an oxidizing atmosphere at 200-800 deg.C reaction temp. in the presence of hydrocarbon of 0.5-200 THC conc./NOX conc.