| Index items | Standard value | Test Results |
| Appearance | White or yellowish crystal powder | Meets the requirement |
| purity | ≥99% | 99.2% |
| PH value | 6.0—8.0 | 6.70 |
| Sulphate | ≤0.05% | 0.03% |
| chloride | ≤0.04% | 0.04% |
| lead,ug/g | ≤2% | 1.38% |
| loss on drying | ≤0.5% | 0.21% |
| Reducing substances | ≤0.7% | 0.38% |