Why cant sodium metabisulfite products last for a long time?

In addition to being used as a food preservative and bleaching agent, sodium metabisulfite is widely used in other industries. Sodium metabisulfite industry can also be used in printing and dyeing, organic synthesis, printing, tanning, pharmaceuticals and other departments. Sodium metabisulfite products are widely used, and the purchase volume of each batch of the enterprise is also large, but here as a professional sodium metabisulfite manufacturer, we remind you that sodium metabisulfite products should not be released for a long time.

Sodium metabisulfite products are white or yellow crystalline powder or small crystals, with a strong SO2 smell, specific gravity 1.4, soluble in water, the aqueous solution is acidic, SO2 will be released in contact with strong acid to form the corresponding salts, if left in the air for a long time, then It is oxidized to Na2S2O4, so the product cannot survive for long. Above 150°C, SO2 is decomposed.

　　Sodium metabisulfite products should be stored in a cool, dry warehouse. The package is sealed and should be protected from air oxidation and moisture. Transportation, storage should prevent damage, moisture, and heat deterioration. The storage period of this product is 6 months from the date of production. It is strictly forbidden to store and transport with acids, oxidants and harmful toxic substances.

Wastewater treatment uses sodium metabisulfite as a white or yellowish powder, used under alkaline conditions, can generate sulfide precipitates with heavy metal ions in wastewater to achieve the purpose of removal. Let's take a look at the treatment of industrial wastewater with sodium metabisulfite:

1.Sodium metabisulfite is a reducing agent and is used to treat chromium-containing wastewater in sewage treatment.

　　 2. Wastewater containing chromium, national standards require that it must be treated separately, and cannot be discharged into a comprehensive pool, and the concentration of hexavalent chromium must not be higher than 0.1.

　　 3. The delivery point of sodium metabisulfite is in the raw water of chromium-containing wastewater, reducing hexavalent chromium to trivalent chromium, and then performing precipitation.

Sodium sulfite is generally used in the wastewater treatment of the electroplating industry. Because the amount of water produced by the wastewater treatment industry is different, generally two or more kinds of agents are used for treatment. The order of the agents can be determined through experiments. Such as wastewater treatment chemicals.