| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing a cerium abrasive of which the contents of alkali metals, alkaline earth metals, and radioactive substances are lowered and which has a fluorine content freely controllable from the viewpoint of lanthanum influence and grinding power. SOLUTION: This cerium abrasive is prepared by chemically separating and removing alkali metals, alkaline earth metals, and radioactive substances to reduce the contents of these substances to produce a light rare earth material which does not contain fluorine and mainly comprises cerium, partially fluorinating the light rare earth material with hydrofluoric acid to produce a fluorinated rare earth, and baking the fluorinated rare earth at a temperature of 600 deg.C-1,000 deg.C. The amount of hydrofluoric acid used is adjusted so that the fluorine contents of the resultant cerium abrasive is enough to convert lanthanum in the light rare earth material into lanthanum fluoride but is insufficient to sinter the fluorinated rare earth during the baking.
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