Basic information 
Molecular formula: \ (\ boldsymbol {NaHSO3} \) 
CAS：7631-90-5 
Nicknames: Sodium bisulfite, Sodium bisulfite 
Appearance: White crystalline powder/particles with a pungent odor of sulfur dioxide; Easy to dissolve in water, the aqueous solution is weakly acidic (1% solution pH 4.0-5.5), and slightly soluble in ethanol. 
Industrial product purity: ≥ 98%; Food grade meets the national standard E222. 
Packaging: 25kg lined with PE woven bag; We can also supply 38-40% liquid sodium bisulfite. 
>The supporting logic for water treatment: sodium hypochlorite (chlorine disinfection) → sodium bisulfite (residual chlorine removal), protects the reverse osmosis membrane and activated carbon, and prevents oxidants from oxidizing and damaging PAM. 
Core Advantages 
1. Efficient dechlorination reducing agent (the main use in water treatment) 
Quickly restore residual chlorine in water, eliminate oxidizing properties, and protect RO membranes, ultrafiltration membranes, and activated carbon from oxidative damage; Fast response speed and controllable dosage. 
2. Antioxidant, bleaching and reducing properties 
Can be used as a reducing agent and antioxidant to inhibit material oxidation and discoloration; Used in the textile and paper industries for dechlorination and decolorization after bleaching. 
3. Cost efficient and easy to add 
Solid is easily soluble, and liquid products can be directly added by metering pumps; Low dosage of medication and high cost-effectiveness of dechlorination. 
4. Can treat some heavy metals and cyanide containing wastewater 
Reduce hexavalent chromium under specific processes for the treatment of chromium containing wastewater; The gold mining industry is used for cyanide detoxification. 
5. Food grade can be used for anti-corrosion and antioxidant purposes 
Used in the food industry as an antioxidant and color protectant (dried fruits, fruit wine) to inhibit oxidative deterioration. 
Main applications 
1. Water treatment industry 
-Wastewater treatment plant tail water, reclaimed water reuse, reverse osmosis pure water system to remove residual chlorine (after disinfection with sodium hypochlorite); 
-Deoxygenation and protective membrane components for circulating water and pure water systems. 
2. Textile printing and dyeing 
Dechlorination agents and dye reducing agents used after fabric bleaching to prevent oxidation and yellowing of the fabric. 
3. Paper industry 
Pulp bleaching, lignin reduction, and removal of residual oxidants after bleaching. 
4. Chemical and pharmaceutical industries 
Reductive agent, acidic drug antioxidant, synthetic intermediate. 
5. Food industry (food grade) 
Dried fruits, wine, and fruit pulp have antioxidant properties, color protection, and anti-corrosion properties.