| Exterior | White flaky crystals |
| Melting point | 270-280°C |
| Solubility | Easily soluble in water, slightly soluble in ethanol and dimethyl sulfoxide, insoluble in other organic solvents |
| Feature | Specification |
| Aqueous solution | Transparent |
| Content | >99.50% |
| Chloride | ≤0.035% |
| Iron | ≤0.4ppm |
| Sulfite | ≤0.02% |
| Moisture | ≤0.5% |
| Chroma | ≤10 |
| Back |