sodium sulfite

Chemical properties

Sodium bisulfite is a white crystalline solid. Slight odor of sulfur dioxide and a disagreeable taste. Slowly oxidized to the sulfate on exposure to air

Potential Exposure

Sodium bisulfite is used in the digestion of wood pulp, in the tanning of leather; in the dyeing of textiles; as a photographic reducing agent; as a food preservative; as an additive in electroplating; as disinfectant, bleach, antioxidant, and as inhibitor of yeast and bacteria in winemaking.

Shipping

UN2693 Bisulfites, inorganic, aqueous solutions, n.o.s., Hazard class: 8; Labels: 8-Corrosive material. UN3260 Bisulfites, inorganic, solid, n.o.s., Hazard class: 8; Labels: 8-Corrosive material.

Incompatibilities

Aqueous solution is a weak acid. Incompatible with strong mineral acids forming a toxic sulfur dioxide gas. A strong reducing agent, sodium bisulfite is incompatible with oxidizers, such as perchlorates, peroxides, permanganates, chlorates, and nitrates. Reacts with bases forming sulfate. Slowly oxidizes to sulfate in air. Heat causes decomposition. Slowly oxidized to the sulfate on exposure to air. Contact with oxidizers or acids forms sulfur dioxide gas. Attacks some metals in the presence of moisture.

Waste Disposal

Dump into water, add soda ash, then neutralize with HCl; flush to sewer with large volumes of water.