Chlorine lime, its physical and chemical properties and application

Chlorine lime is also called white or calcium hypochlorite. Although the latter name is not entirely true, tk. This substance is a complex mixture and includes not only hypochlorite (Ca (ClO) 2), but also oxychloride (CaClO), chloride (CaCl2), and calcium hydroxide (Ca (OH) 2). Ferric chloride is also present as an impurity, which gives a yellowish color. Under normal conditions, this compound has a solid aggregate state, a strong smell of chlorine and, most often, a white color. Only calcium hypochloride dissolves in water, chlorine is released into the atmosphere, and the remaining components of the mixture form a thick precipitate - a slurry.

When direct sunlight hits lime chlorine releases oxygen, and when heated, decomposes with the release of heat, which can lead to an explosion. In this regard, this substance must be stored in dark, cool (unheated) and ventilated rooms. When working with bleach it is necessary to use protective equipment for skin, respiratory organs, especially at the enterprises for its production and transportation.

From the point of view of chemistry, the substance chlorine lime, the formula of which is recorded by CaCl (OCl), refers to mixed (double) salts, i.e. Contains two anions. Also this compound is a strong oxidizer capable of converting MnO (manganese (II) oxide) → MnO2 (manganese oxide (IV)) in an alkaline solution; When interacting with organic substances cause their ignition. In the interaction with sulfuric or hydrochloric acids, chlorine is released: Ca (ClO) Cl + H2SO4 → Cl2 + CaSO4 + H2O.

This substance is produced in the process by chlorination of calcium hydroxide. In this process, chlorine lime is produced in three grades - 26, 32 and 35% active chlorine (the amount of pure chlorine released when HCl or H2SO4 acids act on this mixture). One of the disadvantages of this substance is that it loses active chlorine during storage, 5-10% per year. Struggle with this try, producing a product of increased stability, passing chlorine in the form of gas through a suspension of Ca (OH) 2. The active chlorine in the compound obtained in this way is 45-70%. Also a disadvantage of this substance is that it causes corrosion of metal and corrodes cotton fabrics. Therefore, store it in wooden containers, plastic containers or polyethylene bags and bags.

Chlorine lime shows bactericidal and sporicidal properties, which are determined by the presence of hypochlorous acid and oxygen in the solution. Due to this, it is actively used in sewage treatment from various sewage and medical institutions as a disinfectant (surfaces, public places are treated). Also used as bleach in the manufacture of fabrics, cellulose and paper.

Thus, bleach is a complex mixture, which is a chemically quite active substance and exhibits the properties of a strong oxidizer. In aqueous solutions, it hydrolyzes, forming hypochlorous acid (HC1O). With increasing temperature (heating) and under the influence of sunlight, it decomposes, releasing oxygen and chlorine.