| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing high purity barium nitrate useful for a raw material for optical glass, an optical cable, or a stepper; in which the concentrations of an alkali metal, a transition metal, especially Sr, Ca, Cl, are several ppm or below, and the concentration of Fe is reduced to 100 ppb or below. SOLUTION: The method includes the first process in which crude barium nitrate, an oxidizing agent, and an alkali are dissolved in water, the second process in which insoluble components are removed from a crude barim nitrate aqueous solution obtained in the first process, and the third process in which nitric acid is added to the aqueous solution after the removal of the insoluble components obtained in the second process to deposit barium nitrate to obtain high purity barium nitrate. COPYRIGHT: (C)2003,JPO
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