Sodium metabisulphite is colorless to yellow-colored water purification liquid and produces a sulfurous odor. It is a water-soluble inorganic compound and is made up of oxygen, sulfur, and sodium. It is not itself a disinfectant but after dissolution in water, it is converted to sodium bisulfite. Its optimal use causes the prevention of fungal growth and development in the membranes by causing oxygen scavenging. It also inhibits aerobic bacterial growth in storage conditions and thus protects water from spoilage.
Sodium metabisulfite is also known as sodium pyro sulfite or disodium metabisulfite and is being commonly used as a preservative, antioxidant, and disinfecting agent.
It is recommended to keep it away from direct sunlight and heat as direct exposure to heat can cause the release of fumes of sulfur dioxide (SO2). Moreover, the solution must also be protected from freezing to avoid any effects on its quality. It has much lesser toxicity levels and thus is safe to use followed by the right care and management measures. The use of safety goggles, rubber gloves, and protective clothing is greatly recommended to avoid any hazards associated with accidental splashing and spillage.
It is safe to use chemicals for water purification but may cause some kind of allergic reactions to people who have sulfites sensitivity. Generally, the solutions of sodium metabisulfite have a short shelf life and can easily react with oxygen and chlorine. So, it can also be used for the neutralization of chlorine so its dosage should be carefully applied to the down streams of the cartridge of filters so that disinfection of cartridge can also occur due to chlorine. The optimal dosage of sodium metabisulfite solution is also important for the proper functioning of RO filtration systems. Whereas inline mixing can be enhanced by using a static mixer.