Quality standard:

National standard

Molecular formula:

Na2S2O5

Relative molecular weight:

190.10

Property:

 It is white or yellowish crystalline powder with strong SO2 odor; specific wt.: 1.4. soluble in water, its aqueous solution is acidic.

Use:

Mainly used in  printing & dyeing; as dechlorinating agent for textile bleaching; as reducing agent and sulfonating agent for chemical and medical industries, food activities etc.

Item

Specification

Test result

Remarkes

Sodium metabisulfite

97min.

97.83%

Sulfur Dioxide(SO2)

65%max.

65.78%

Arsenic(As)

0.0002%max

0.00011%

Selenium(Se)

0.0005%max

0.00009%

Heavy Metals(As Pb)

0.0005%max

0.0003%

water Insoluble

0.02%max

 0.016%

Iron(Fe)

0.002%max

 0.001%

 PH Value

4.0-4.8 

 4.4