Sodium metabisulfite is white or yellow crystalline powder or small crystal, with a strong SO2 odor, soluble in water, the aqueous solution is acidic, when contacted with strong acid, SO2 is released to form corresponding salts, and it is oxidized to Na2S2O6 when placed in the air for a long time. Therefore, the product cannot be stored for a long time. Above 150 degrees Celsius, SO2 is decomposed.
Specification

TEST ITEMS
TEST STANDARD
Na2S2O5 %
96.5
FERRON(Fe) %
0.005
WATER INSOLUBLE %
0.05
ARSENIC(As) %
0.0001
HEAVY METAL(Pb) %
0.0005
Application

Use 1
Used as a coagulant in the rubber industry.
Use 2
Used as chromatographic reagents, preservatives and reducing agents in the dye and pharmaceutical industries.
Use 3
In the food industry, it is used as bleaching agent, preservative, bulking agent, antioxidant, color retention agent and
preservative.
Use 4
In the printing and dyeing industry, it is used as a dechlorination agent for cotton cloth after bleaching, and as a cotton
scouring aid.
Use 5
The tanning industry is used for leather processing.
Use 6
The chemical industry is used to produce hydroxyvanillin, hydroxylamine hydrochloride, etc. The photosensitive industry is used as developer and so on.