Calcium hypochlorite bleach liquor

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. 

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

While there are many chemicals in use, the term bleach syn. bleach solution commonly means a hypochlorite, principally sodium hypochlorite, a common household bleach, but also calcium, magnesium, and lithium hypochlorites. Bleach liquor is a solution of calcium hypochlorite and calcium chloride commonly used to bleach paper pulp. Hypochlorite solutions are alkaline, only remaining stable above the pH of 11. 

Bleach Liquor. Bleach Hquor or lime bleach Hquor is an aqueous solution of calcium hypochlorite and calcium chloride. It typically contains 30—35 g/L of available chlorine, though it may be as high as 85 g/L. It has been used in pulp bleaching, when it can be made more cheaply than sodium hypochlorite. It is prepared on site by chlorinating lime solutions. 

In addition to soln. of chloride of lime—lime bleach liquor—bleaching liquids with magnesium, zinc, or aluminium hypochlorites as the active agents have also been made and special virtues claimed for their use. For example, if magnesium sulphate be added to a soln. of bleaching powder, calcium sulphate is precipitated and a soln.—magnesia bleach liquor—of magnesium hypochlorite can be decanted off similarly with zinc hypochlorite—zinc bleach liquor and with aluminium hypochlorite—alumina bleach liquor, or Wilson s bleach liquor. 

Chromate cannot be added to bleaching liquors used for the treatment of textiles, as it stains them and can be removed only with great difficulty. In this case the cathodic reduction of hypochlorite can be partially suppressed by the addition of calcium chloride together with high molecular aliphatic compounds... 

Two general types of bleaches have been used in ADDs hypochlorite and peroxygen bleaches. Chlorine bleaches refer here to complexes that either contain or deliver hypochlorite (OC1-) in solution. The compounds used in detergent products are typically alkali metal or alkaline earth hypochlorites, with liquid sodium hypochlorite being the most common. Solid calcium hypochlorite has also received attention, although its low solubility and its contribution of Ca2+ to the wash liquor has limited its use in LADD products. Generally, NaOCl is added in amounts resulting in 1 to 2% available chlorine. 

Calcium hypochlorite 4245 CaOCU Bleaching liquor bleaching powder chloride of lime chlorinated lime oxymurlate of lime. 

Oven-dried cotton contains about 90% cellulose whilst cotton linters contain 80-85%. In the preparation of chemical cellulose, cotton linters are processed in the following manner. Firstly, the linters are heated at 130-180°C under pressure with 2-5% aqueous sodium hydroxide for 2-6 hours this treatment solubilizes particles of seed-hull and other contaminants present in the linters. The liquor is drained off. The residual linters are washed with water, bleached with gaseous chlorine or calcium hypochlorite, re-washed and dried at about 70°C. The final product has a cellulose content of about 99%. 

A normal liquor made up with bleaching powder will have an initial pH of 11-05, and when sodium hypochlorite is used it will be 11-55. In each case the pH falls during j, ing and with subsequent bleaches when standing baths are used. 1. unospheric carbon dioxide forms insoluble calcium carbonate with bleaching powder and soluble alkaline sodium carbonate with sodium hypochlorite. The risk that the pH may fall below the... 

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