Calcium hypochlorite is also called chlorinated lime and bleaching powder. White powder with strong chlorine odor. Its solution is a yellow green translucent liquid. Melting point 100 ℃ (decomposition), soluble in water, relative density (water = 1) 2.35, relative density (air = 1) 6.9. It is a strong oxidant, which can heat and self ignite when mixed with organic matter and flammable liquid, and explode when exposed to high heat. When exposed to air, it is easy to absorb water and carbon dioxide, which liberates hypochlorite and chlorine. Hypochlorite is then decomposed to produce hydrogen chloride and new oxygen. The new oxygen has strong oxidizing power and the ability to destroy the pigment group, fade the colored materials and achieve the bleaching effect. Have the ability of disinfection and sterilization. Dissolve in water and react in an alkaline way. The composition contains calcium chloride, which is easy to absorb moisture, so the property is very unstable. After long-term storage, even without air and water, it can decompose itself and reduce its effective composition.

      Production process of calcium hypochlorite: (1) caustic soda lime chlorination method: add sodium hydroxide into lime milk Ca (OH) 2, chlorinate with chlorine gas, precipitate and precipitate Ca (CLO) 2 · NaClO · NaCl · 12H2O triple salt crystallization. When the molar ratio of calcium chloride to sodium hypochlorite in trimer salt reaches 1:2, all sodium hypochlorite is converted into calcium hypochlorite. (2) Lime chlorination: it is made by the interaction of lime milk and chlorine gas. According to the change of lime milk concentration and chlorination conditions, different purity products can be obtained. (3) Lime hypochlorite neutralization: it is made by neutralizing hypochlorite with calcium hydroxide (solid or slurry).

Use of calcium hypochlorite:

It is mainly used for bleaching paper, cotton, hemp, silk fiber and fabric, disinfection of urban and rural drinking water and swimming pool water, etc.

In agriculture, it is used as disinfectant for silkworm rooms, ponds, livestock houses, etc.

The chemical industry is used for the purification of acetylene and the manufacture of organic compounds. Chloroform can be produced by the reaction of the aqueous solution of bleaching powder with ethanol, acetone, acetaldehyde, etc.

In addition, it is also used as shrinkproof agent and deodorizer for wool.