项 目 | 医药级 | 食用级 | 工业级 |
外观 | 白色结晶 | 白色结晶 | 白色结晶 |
含量 | ≥98.0% | 96.0-101.0% | 98.0-101.0% |
PH 值 5% 水溶液25°C |
6.7-7.3 | 6.7-7.3 | 6.7-7.3 |
氯化物(Cl) | ≤0.0005% | ≤0.005% | ≤0.005% |
重金属(as Pb) | ≤0.001% | ≤0.0005% | ≤0.0005% |
铁 | ≤0.001 % | ≤0.001% | ≤0.001% |
水不溶物 | ≤0.005% | --- | --- |
燃烧残渣 | ≤0.01% | --- | --- |
硫酸盐(SO4) | ≤0.005% | --- | --- |