Sodium Metabisulphite (Na2S2O5)

Sodium Metabisulphite (Na2S2O5) is a white to yellowish crystalline powder supplied typically at a purity level suitable for industrial applications, commonly 96% minimum. It acts as a strong reducing agent and preservative, dissolving readily in water to yield sulfur dioxide, which imparts its functional chemical properties. Buyers handling this chemical should note it has acidic to neutral pH in aqueous solutions, and it decomposes upon heating above 150°C, releasing sulfur dioxide gas that requires proper ventilation. This compound is commonly sourced in granular or powder form, packaged in multi-kilogram bags to facilitate dosing and handling in various industrial processes. Typical usage concentrations vary but, for example, in water treatment processes, a dosage rate between 10 and 100 mg/L is standard to effectively remove residual chlorine. It is important to avoid mixing Sodium Metabisulphite directly with strong oxidizing agents, as this can lead to hazardous reactions. Storage conditions require cool, dry, and well-ventilated areas to maintain its stability and prevent premature decomposition.

In water treatment, residual chlorine can be harmful to equipment and downstream processes. Sodium Metabisulphite effectively neutralizes chlorine by chemical reduction, preventing corrosion and protecting sensitive biological treatment stages. This ensures system longevity and maintains water quality meeting required standards. In the food industry, oxidation leads to spoilage and discoloration of products. Sodium Metabisulphite serves as an antioxidant preservative that extends shelf life by scavenging oxygen and inhibiting enzymatic browning. This stabilizes food quality during storage and processing, which is critical for maintaining product safety and consumer acceptance.