33060 ⎘
Catalysts comprising molecular sieves having base-exchange properties, e.g. crystalline zeolites; Crystalline aluminosilicate zeolites; Isomorphous compounds thereof of types characterised by their specific structure not provided for in groups - containing arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium MAZ-type, e.g. Mazzite, Omega, ZSM-4 or LZ-202