| ITEM | STANDARD |
| Appearance | A white or almost white crystalline powder |
| Identification | Comply with |
| Melting Point | 164.5~166.5 |
| Assay | >=99.0% |
| Loss on drying | =<0.5% |
| Chloride | =<0.035% |
| Heavy metals | =<10PPM |
| Iron | =<40PPM |
| Residue on ignition | =<0.1% |
| Alkali-insoluble | Clear |