| 摘要 |
The residue separated from the solution after dissolving the crude phosphate in nitric acid is washed with nitric acid to remove the remainder of the digestion product. It is then mixed to a suspension with H2O and ammonia led in at 40-110 degrees C.M preferably 80-100 degrees C., to give pH >2.0, preferably 4.0-7.0. The solid material is separated from the liquid and into the latter are passed NH3 +CO2 in a molar ratio 2 : 1, at 30-100 degrees C., preferably 60-65 degrees C., until precipitation of strontium carbonate is complete. |
