Method for preparing fluorination catalyst used to fluorinate halogenated hydrocarbons
AssigneeDaikin Industries, Ltd.
InventorsTakashi Shibanuma, Yoshio Iwai, Satoshi Koyama
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Abstract
A method for preparing a fluorination catalyst is disclosed, wherein the catalyst contains chromium oxide, has a specific surface area of from 170 m.sup.2 g to 300 m.sup.2 /g, catalyzes the fluorination of a halogenated hydrocarbon with hydrogen fluoride, and has a high activity and long catalyst life. The method includes mixing an aqueous solution of a chromium salt with aqueous ammonia to precipitate chromium hydroxide, drying the precipitated chromium hydroxide, sintering the dried chromium hydroxide, and fluorinating the sintered chromium hydroxide to obtain the chromium oxide catalyst.
Claims8
A method for preparing a fluorination catalyst which consists essentially of the steps of:
- mixing an aqueous solution of a chromium salt with aqueous ammonia to precipitate chromium hydroxide,
- drying the precipitated chromium hydroxide,
- sintering the dried chromium hydroxide to obtain chromium oxide having a specific surface area of 170 m.sup.2 /g to 300 m.sup.2 /g, and
- fluorinating the chromium oxide to obtain the chromium oxide catalyst having a fluorine content of at least 8%.
Dependencies are inferred from the claim text.