Sodium bisulfite is used for the bleaching of cotton fabrics and organic materials; and used as a reducing agent in dyestuff, papermaking, tanning, chemical synthesis and other industries. In the pharmaceutical industry, it is applied to produce intermediates of metamizole and aminopyrine; serves as bleaching agent, preservative, and antioxidant food grade products, and used as a plating additive in the treatment of chromium-containing waste water.