Document Type and Number:
Japanese Patent JPS6363487
Kind Code:
B2
Abstract:
PURPOSE:To prepare fine powder of rare earth element oxide having large specific surface area, by reacting an aqueous solution of rare earth element salt with oxalic acid in a solid state to give an oxalate, decomposing it thermally in the presence of steam under specific conditions. CONSTITUTION:An aqueous solution of rare earth element salt is reacted with oxalic acid in a solid state or ammonium oxalate in a solid state, and fine precipitate of rare earth element oxalate is formed. The precipitate of rare earth element oxalate is heated in the presence of steam at <=200 deg.C->=650 deg.C, preferably at 300-550 deg.C for 10min - tens hours. Since formed fine powder of rare earth element oxide is active and it specific surface area is gradually reduced in an atmosphere, it is stored in a hermetically sealed container until immeduately before use.
Application Number:
JP2078584A
Publication Date:
December 07, 1988
Filing Date:
February 09, 1984
Export Citation:
International Classes:
C07C55/07; C01F17/00; C07C51/00; C07C67/00
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