Item

Standard

Industrial grade

Food grade

Refining grade

Identifications

Meet the specifications

Meet the specifications

Meet the specifications

Assay, %

≥ 98.0

98.0 ～ 102.0

99.0 ～ 102.0

Drying loss, %

≤ 0.50

≤ 0.30

≤ 0.30

Heavy metal, μg/g

≤ 10

≤ 10

≤ 10

Sulphate, %

≤ 0.05

≤ 0.05

≤ 0.05

Chloride, %

≤ 0.07

≤ 0.07

≤ 0.07

Reduzate, %

≤ 0.70

≤ 0.50

≤ 0.50

Lead, μg/g

≤ 2

≤ 1

≤ 1

Solubility(1.0g , 10ml water)

Colorless, almost clear

Colorless, almost clear

PH

6.2 ～ 7.8

6.2 ～ 7.8

6.2 ～ 7.8

Arsenic salt, μg/g

≤ 2

≤ 2