It is used as preservative, bleach and loosening agent in food processing. In industry, sodium pyrosulfite is used in printing and dyeing, organic synthesis, printing, tanning, pharmaceutical and other departments; Sodium pyrosulfite is used in the chemical and pharmaceutical industries for the production of insurance powder, sulfamethazine, analgin, caprolactam, etc., as well as the purification of chloroform, phenylpropanesulfone and benzene formaldehyde. The photographic industry is used as an ingredient for fixing agents. Perfume industry is used to produce vanillin. It is used as preservative in brewing industry, rubber coagulant and dechlorination agent after cotton bleaching. Organic intermediates, dyes and tanning are used as reducing agents, electroplating industry, oilfield wastewater treatment and mineral dressing agent in mines.
CAS No.
7681-57-4
Formula
Na2O5S2
Molecular Mass
190.10700
Exact Mass
189.89800
PSA
124.92000
Logp
0.27220
IUPAC
Sodium metabisulfite
Attribute classification
Matter Classification
inorganic
Category
Chemical and Physical Properties
Melting Point
150 °C
Density
1.48
Appearance
White or yellow crystalline powder or small crystals