Item |
Superfine Grade |
First grade |
Qualified grade |
Purity≥ |
99.5% |
99.0% |
98.0% |
Moisture≤ |
0.30% |
0.50% |
0.80% |
Water insoluble substances≤ |
0.01% |
0.03% |
0.03% |
Sulfate(SO4)≤ |
0.01% |
0.02% |
0.02% |
Fe≤ |
0.005% |
0.03% |
0.05% |
Cl≤ |
0.15% |
0.20% |
0.30% |