| 摘要 |
PURPOSE:To obtain a ternary catalyst having high activity even in the presence of a large amt. of oxygen by using crystalline silicate having a specified composition and crystal structure and allowing copper and other specified active metal to coexist. CONSTITUTION:The crystalline silicate used has the x-ray diffraction property as shown in Table (A) and its composition is expressed by the molar ratio of oxides in a dehydrated state as [(1.0+ or -0.8)R2O.>=aM2O3.bAl2O3].ySiO2, wherein ar is alkali metal and/or hydrogen, M is group VIII metal or rare earth metal, a+b=1, a>=0, b>=0, y>11. Then copper and specified metal such as Mg, Ba, etc., are made to coexist in this silicate. Thereby, Cu on the silicate activates CO and hydrocarbon to effect the reaction of these gases with NO to remove NOX. Moreover, coexistence of other metal improves heat resistance of Cu and selectivity of denitration reaction is improved. |
