Specification
| Appearance | White or yellowish powder | White powder |
| Identification | Infrared identification: The infrared absorption spectrum of the sample should be consister with that of the reference substance | Conform |
| Assay(HPLC,dry basis) | ≥98.0% | 99.1% |
| Active matter | ≥45.0% | 54.2% |
| Water | ≤11.0% | 10.1% |
| pH(3% aqueous solution) | 9.0-10.0 | 9.2 |
| Clarity and color of solution(3% aqueous solution) | Clear and almost colourless | Conform |
| Free phosphoric acid | ≤0.5% | <0.5% |
| Chloride | ≤0.035% | <0.035% |