Prodn. of a Cu-contg. zeolite catalyst for purificn. of effluent gases by removal of nitrogen oxides NOx with ammonia and/or urea, comprises treating a hydrophobic, dealuminated Y-type zeolite with a modulus of 100 or more, pref. 200 or more, and with a pore size of 7.4 ?A, with an aq. soln. of a Cu cpd., esp. Cu chloride, removing the moist zeolite from the soln. and drying at 110-200 deg C. The dried zeolite may subsequently be treated at 250-400 (300) deg C with a steam- and oxygen contg. gas.
展开▼