Bleaching chlorine

The presence of chloric(I) acid makes the properties of chlorine water different from those of gaseous chlorine, just as aqueous sulphur dioxide is very different from the gas. Chloric(I) acid is a strong oxidising agent, and in acid solution will even oxidise sulphur to sulphuric acid however, the concentration of free chloric(I) acid in chlorine water is often low and oxidation reactions are not always complete. Nevertheless when chlorine bleaches moist litmus, it is the chloric(I) acid which is formed that produces the bleaching. The reaction of chlorine gas with aqueous bromide or iodide ions which causes displacement of bromine or iodine (see below) may also involve the reaction... 

Chemical Properties. Under slightly acidic or basic conditions at room temperature, acetate and triacetate fibers are resistant to chlorine bleach at the concentrations normally used in laundering. 

International Non-Chlorine Bleaching Conference, Amelia Island, Ela., Mar. 1994 and 1995 International Pulp Bleaching Conference, Vancouver, B.C.,June 1994. 

Substitution of chlorine dioxide for chlorine in the first (chlorination) bleaching stage (C ) is a strategy that has been widely adopted in North... 

Miscellaneous. In ore flotation, sodium sulfite functions as a selective depressant. In textile processing, sodium sulfite is used as a bleach for wood (qv) and polyamide fibers and as an antichlor after the use of chlorine bleach. Synthetic appHcations of sodium sulfite include production of sodium thiosulfite by addition of sulfur and the introduction of sulfonate groups into dyestuffs and other organic products. Sodium sulfite is useful as a scavenger for formaldehyde in aminoplast—wood compositions, and as a buffer in chrome tanning of leather. 

The actual form of an available chlorine bleach in solution must be determined from equations 1—4. The equiUbrium constants for equations 2 and 3 are 3.94 x 10 (9) and 2.88 x 10 M (10) at 25°C, respectively. Thus, above pH 9.5 more than 99% of the available chlorine is present as... 

Solutions of available chlorine bleaches decompose on standing at a rate that depends on the conditions described below. Hypochlorous acid [7790-92-3] and hypochlorite anions decompose according to equations 6 and 7 (20,21) ... 

Commercially important soHd available chlorine bleaches are usually more stable than concentrated hypochlorite solutions. They decompose very slowly in sealed containers. But most of them decompose quickly as they absorb moisture from air or from other ingredients in a formulation. This may release hypochlorite that destroys other ingredients as well. 

In industrial and institutional bleaching either Hquid or dry chlorine bleaches are used because of their effectiveness, low cost, and germicidal properties. Dry chlorine bleaches, particularly formulated chloroisocyanurates, are used in institutional laundries. 

M Practical Guide to Chlorine Bleach Making, Technical and Engineering Seivice Bulletin 72-19, AUied Chem. Coip., Moiristown, N.J., 1974 Soda Bleach Solutions, Diamond Alkah Co., 1952. 

Oxidation. Oxidation is one of the main chemical methods to treat and decompose dyes in wastewater. The oxidation agents used ate chlorine, bleach, ozone, hydrogen peroxide, Fenton s reagent, and potassium permanganate. 

Earlier formulations contained mainly chlorine bleach, metasiUcates, triphosphate, and nonionic surfactants. Modem manufacturers have switched to more compHcated formulations with disiUcates, phosphates or citrate, phosphonates, polycarboxylates, nonionic surfactants, oxygen bleach, bleach activator, and enzymes. The replacement of metasiUcates by disilicates lowers pH from approximately 12 to 10.5, at 1 g ADD/L water. The combined effect of decreased pH, the absence of hypochlorite, and the trend toward lower wash temperatures has paved the way for the introduction of enzymes into ADDs. Most ADD brands in Europe are part of the new generation of ADD products with enzymes. The new formulations are described in the patent hterature (55—57). 

Technical, economic, and environmental advantages exist for ozone bleaching of pulp in the paper industry as an alternate to hypochlorite or chlorine bleaching which yields deleterious compounds to the environment. 

Chlorid, n. chloride (esp., an -ic chloride, as contrasted with Chloriir). -chlor, n. chlorine in the form of chloride. chLoridhaltlg, a. containing chloride(s). Chloridlauge, /. chloride solution, chlorierbar, a. capable of chlorination, chlorieren, c.f. chlorinate Bleaching) chemick ... 

Sodagehalt, m. soda content, sodahaltig, a. containing soda. Sodakochchlorblelche, /. boiling soda-chlorine bleach. 

Daily bathing (showering is best) is recommended. Disinfect toilet facilities daily, and disinfect the bathtub or shower stall immediately after bathing. Use the disinfectant recommended by the primary health care provider or use chlorine bleach. Scrub the surfaces thoroughly and allow the disinfectant to remain in contact with the surfaces for several minutes. 

Sodium hypochlorite is the main ingredient in laundry bleach. Despite the fact that it is commonly referred to as chlorine bleach, in normal use there is no chlorine gas involved in the action of bleaching or disinfecting. 

Laundry bleaches fall into two categories. The first is what are called chlorine bleaches. The second is oxygen bleaches. 

Another chlorine bleach in common use is sodium dichloroisocyanurate. 

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