| 摘要 |
PROBLEM TO BE SOLVED: To provide a method capable of inexpensively producing a hydrogen phosphate alkali metal salt and a condensed phosphoric acid alkali metal salt excellent in treatability (handling properties).SOLUTION: A phosphoric acid aqueous solution with a prescribed concentration subjected to stirring treatment is added with an alkali metal carbonate in a prescribed ratio, and stirring treatment is continued till the reaction between the phosphoric acid aqueous solution and the alkali metal carbonate is completed to obtain a hydrogen phosphate alkali metal salt. This is dried under the reduced pressure of 17.3 kPa abs or lower and is thereafter heated to obtain a reduced alkali phosphate metal salt.SELECTED DRAWING: None |
