Water Treatment Chemical Sodium Hypochlorite

1. Characteristics

Sodium hypochlorite is also known as sodium hypochlorite, bleach (liquid), and antiformin (aqueous solution), and its molecular formula is NaClO. Sodium hypochlorite anhydrous is a white crystalline powder, which is extremely unstable. It decomposes rapidly when heated and deliquesces when exposed to water, but is relatively stable in an alkaline state. NaCIO solution is a colorless or light yellow liquid. Its stability is affected by pH, light, temperature and heavy metal ions. It is easily soluble in water and generates caustic soda and unstable hypochlorous acid. The use of hypochlorous acid can avoid problems such as cylinder pressure, air leakage and pipeline corrosion caused by the use of liquid chlorine.

2. Mechanism of action

NaClO dissolves in water to produce hypochlorous acid, which has the same bactericidal effect as chlorine.

3.Use

NaCIO is a strong oxidizing agent with bleaching, sterilizing, and disinfecting effects. It can be used as a bleaching agent, oxidizing agent, and water purifier in papermaking, textiles, light industry, etc. It can also be used as a disinfectant and in the pharmaceutical industry. Chloramine production, etc.

4. How to use

When using NaClO, for a system with a small amount of water, it can be added directly; for a circulating system with a large amount of water, an automatic dosing system can be used, that is, NaCIO is first prepared into a solution of a certain concentration, stored in the dosing tank, and used Turn on the dosing pump and dose quantitatively. The residual chlorine generated after NaCIO is added to the system lasts relatively short, and is mostly used in systems with low chlorine consumption. The dosage is generally 100mg/L. Under higher pH conditions, NaCIO exists as ClO, and the bactericidal effect is relatively poor. It is recommended to control the pH value of the system below 6.0 during use. High-concentration NaClO has a good stripping effect on slime, but because it is corrosive, it must be used in conjunction with corrosion inhibitors such as chromate or polyphosphate. The dosage depends on the amount of slime.

5. Precautions

NaCIO mostly exists in the form of ClO, and its bactericidal effect is not as good as that of hypochlorous acid. When added to the system, the pH value of the system water should be controlled at 6.0 to 7.0. Because low pH is conducive to the formation of hypochlorous acid, it can improve the bactericidal effect. NaCIO is toxic and inedible. Regular direct contact with NaCIO will cause excessive sweating on the palms, thinning of nails, and hair loss; free chlorine can cause poisoning. Workers who come into contact with NaCIO should wear prescribed labor protection equipment to prevent NaClO from contacting the skin or entering the human body. If NaClO accidentally contacts the skin or enters the human body, rinse or rinse with NaHCO solution immediately.