Calcium hypochlorite bleaches

Bleaching powder, also known as chloride of lime, is produced by reacting hydrated lime with chlorine. It consists of a mixture of calcium hypochlorite (Ca(OCl)2 — the active ingredient), calcium chloride, calcium hydroxide and water. Some processes convert 40 % of the calcium hydroxide, giving about 25 % of available chlorine . Others continue chlorination to completion, which corresponds to 60% conversion and about 36% of available chlorine [31.3]. The reaction (31.1) is surprisingly complex. It is exothermic and drives off excess water. The product is dried under vacuum at temperatures below 85 °C. 

Tropical bleach is produced by blending bleaching powder with finely divided quicklime which converts any free water into calcium hydroxide. The resulting product is stable at temperatures up to 100 °C. 

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Calcium Hypochlorite (Bleach Liquor). Bleach hquor is a solution of Ca(OCl)2 and CaCl2 containing some dissolvedhme. The av CI2... 

About 93% of the CaCOs mud is dried and lecalcined in rotary kilns to recover the CaO. Calcium hypochlorite bleaching liquor (p. 860) for paper pulp is obtained by reacting lime and CI2. 

Sodium hypochlorite is commercially available as an alkaline solution, normally containing the equivalent of 12-14% available chlorine. However, this is so unstable that analytical testing of its strength is always necessary before use. Calcium hypochlorite (bleaching powder), stabilised by adding lime, has been used in the past but this product is no longer used in textile bleaching. 

Othei hypochlorites include calcium hypochlorite, bleach liquor, bleaching powder and tropical bleach, dibasic magnesium hypochlorite, lithium hypochlorite, chlorinated tnsodium phosphate, and hypochlorous acid. 

Summary Chloroform is prepared by reacting acetone with calcium hypochlorite (bleaching powder), and then extracting the mixture with benzene, toluene, or xylene. After extraction, the solvent/chloroform mixture is then distilled to collect the chloroform, which is then re-distilled. After collecting the chloroform after re-distillation, it is mixed with a small amount of 95% ethanol to act as a stabilizing agent. 

Chlorine gas. This gas is available commercially in steel cylinders and should be taken from these. Alternatively, it can be produced in a Kipp apparatus (with glass joints only) from calcium hypochlorite (bleaching powder) and 1 1 hydrochloric acid. It is advisable to mix the bleaching powder with some gypsum powder, making the mixture wet, to produce lumps of the reagent. After drying these lumps can be placed into the Kipp apparatus. 

Acetic Anhydride U u Calcium Hypochlorite Bleach Sol n. s Ethyt Chloride u u... 

Calcium Hypochlorite Bleach - 6SS6 18-30 - E - - Spray drying (180 grams/Nter CaOCi ). AHoy C 0.07 mpy... 

As reagent, a saturated aqueous solution of calcium hypochlorite [bleaching powder, Ca(OCl)2] or a dilute aqueous solution of sodium hypochlorite (NaOCl) is employed. Some commercial bleaching fluids, containing active chlorine, can be used as substitutes.TheCa(OCl)2andNaOClsolutions must be prepared daily, since they decompose within 24-48 hours. In sunlight, they are stable for less than 1 hour. The stock chemicals are best stored in a cool dry place. Light, heat, humidity, and carbon dioxide hasten their decomposition. 

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