Sodium Hydroxide

Sodium hydroxide, with the chemical formula NaOH, commonly known as caustic soda, lye, or sodium hydroxide, emits an ammonia odor when dissolved. It is a highly corrosive strong alkali, generally available in lumps, flakes, granules, and rods. It is readily soluble in water (dissolving exothermically) to form an alkaline solution. It is also hygroscopic, readily absorbing water vapor (deliquescence) and carbon dioxide (deterioration) from the air.

NaOH is an essential chemical in chemical laboratories and a common chemical product. Pure NaOH is a colorless, transparent crystal. Its density is 2.130 g/cm³. Its melting point is 318.4℃, and its boiling point is 1390℃. Industrial NaOH contains small amounts of sodium chloride and sodium carbonate and is a white, opaque crystal.

Sodium hydroxide (NaOH) has a wide range of applications. It is used in papermaking, soap making, dyeing, rayon production, aluminum production, petroleum refining, cotton textile finishing, coal tar product purification, food processing, wood processing, and the machinery industry.

Sodium hydroxide is used in wastewater treatment plants to reduce water hardness through neutralization reactions. In industrial applications, it is a regenerator for ion exchange resins. Sodium hydroxide is strongly alkaline and has relatively high solubility in water. Because of its high solubility in water, the dosage of sodium hydroxide is easy to measure, making it conveniently used in various areas of water treatment.