【CAS】7681-57-4
Alias: Sodium metabisulfite
Molecular formula: Na2S2O5 Relative molecular mass: 190.107
Structural formula:
1.Product Property
Sodium Metabisulfite (chemical formula Na₂S₂O₅) is a white or slightly yellow crystalline powder with a strong SO₂ odor. It is mainly used as a food preservative (E223), and is widely employed in wine production, fruit and vegetable preservation, and dried fruit processing. It is also used in water treatment (dechlorination), textile printing and dyeing (reducing agent), and chemical production.
2.
| Parameter | Industrial Grade | Food Grade |
| Purity (Na₂S₂O₅) | ≥95.0% | ≥96.0% |
| SO₂ Content | ≥64.0% | ≥65.0% |
| Iron (Fe) | ≤0.005% | ≤0.002% |
| Heavy Metals (Pb) | ≤10 ppm | ≤5 ppm |
| Water Insolubles | ≤0.05% | ≤0.02% |
| pH (10% solution) | 3.5–5.0 | 4.0–4.5 |
3.Application scope and Usage
It is used for the production of sodium hydroxide, sulfadimidine, paracetamol, caprolactam, etc.; it is used for the purification of chloroform, benzophenone and benzaldehyde. In the photography industry, it is used as a component of the fixing agent; in the perfume industry, it is used to produce vanillin; it is used as a preservative in the brewing industry; as a rubber setting agent and a chlorine remover after cotton fabric bleaching; as an organic intermediate; for dyeing and tanning; as a reducing agent; used in the electroplating industry, oil fields’ wastewater treatment and as a mineral separation agent in mines; in food processing, it is used as a preservative, bleaching agent and leavening agent.
4.Package and Storage
Packaged in plastic woven bags lined with polyethylene plastic bags, each bag weighs 25kg or 50kg. It should be stored in a cool and dry warehouse. The packaging should be sealed to prevent oxidation by air. Pay attention to moisture prevention. During transportation, it should be protected from rain and direct sunlight. It is strictly prohibited to store and transport together with acids, oxidants and harmful and toxic substances. This product is not suitable for long-term storage. During loading and unloading, handle with care and prevent the packaging from breaking. From the date of production, the storage period of this product is 6 months.
