Caustic Soda

Caustic soda (sodium hydroxide, NaOH, CAS 1310-73-2) is a strongly alkaline inorganic chemical produced in the chlor-alkali process alongside chlorine and hydrogen. It is supplied as solid flakes or pearls at 99% / 96% purity, or as aqueous solution at 32% and 50% concentration. Caustic soda is highly hygroscopic and corrosive, requiring steel or HDPE packaging and careful handling. Its largest consumers are alumina refining, pulp and paper digestion, textile mercerising, soap and detergent manufacture, water treatment pH control and petroleum refining. Industrial, rayon-grade and food-grade (E524) specifications differ mainly in iron, chloride and heavy-metal limits.