METHOD FOR PRODUCING CHA-TYPE ZEOLITE HAVING HIGH Si/Al RATIO

摘要

PROBLEM TO BE SOLVED: To provide a method capable of producing a CHA-type zeolite having an Si/Al ratio of 110 or more, especially 140 or more without depending on a fluoride method since CHA-type zeolite crystals having a Si/Al ratio of 110 or more have not been conventionally produced by a method other than a fluoride method.SOLUTION: There is provided a method capable of producing a CHA-type zeolite having an Si/Al ratio of 110 or more which comprises subjecting a raw material mixture to hydrothermal treatment under conditions at a temperature of 140 to 200°C, wherein the raw material mixture has an Si/Al ratio of 200 or more and contains 0.1 to 5 wt.% of a CHA-type zeolite having an Si/Al ratio of 80 or more as seed crystals based on the silica source (in terms of SiO).SELECTED DRAWING: None