Chlorine as an oxidant

Chlorine dioxide yields of 95% or greater have been demonstrated. The use of chlorine as an oxidant has distinct advantages because it is usually present in municipal water treatment plants for water disinfection. 

The use of chlorine as an oxidizing agent for the conversion of sulphoxides into sulphones is completely unsuccessful under anhydrous conditions. In aqueous solutions, the sulphone is formed but this is usually part of a complex mixture of chlorinated sulphoxides, chlorinated sulphones and sulphonyl chlorides89, so that the reaction is usually not very useful as a preparative method for alkyl sulphones. Dimethyl sulphone has however been obtained in 70% yield in one isolated case90. In methanol solution dibenzyl sulphoxide is cleanly oxidized to dibenzyl sulphone and benzyl sulphonyl chloride in reasonable overall yield91. 

The use of chlorine as an oxidant was investigated by Hlasiwetz and Habermann D-glucose was converted to D-gluconic acid and isolated... 

Addition Products.—The halogen addition products of naphthalene ,re more easily formed than are the substitution products. The tetra-chlor compound is of special interest and has been referred to. We have stated that naphthalene is oxidized to or//fo-phthalic acid. This oxidation was originally carried out not with naphthalene itself but with naphthalene tetra-chloride, CioHgCU. When naphthalene is treated with chlorine (potassium chlorate, KCIO3 and hydrochloric acid HCl), addition takes place and the tetra-chlor addition product is formed. By the further action of the chlorine, as an oxidizing agent, the tetra-chloride is converted into ortho-phthalic acid. 

Gas phase explosion hazard with chlorine as an oxidizer is present in gas phase chlorination processes as well as in chlorinations in the condensed phase. 

A new explosion vessel, a 20 litre sphere, was built to investigate gas phase explosions with special attention for experiments using chlorine as an oxidizer (Fig. 1). 

In certain applications ozone is considered as an alternative to chlorine as an oxidant for cyanide because of the potential for undesirable formation of chlorine compounds with the latter. 

Sodium hypochlorite solutions are used extensively in swimming pool sanitation and as a bleach in the pulp and textile industries. A less-concentrated product (5% available chlorine) is used in laundries and as household bleach. Consumption statistics for 1982 indicate that 210 x 10 tons of sodium hypochlorite were consumed in the United States alone. World consumption of soium hypochlorite for household use is estimated to be 426 X 10 metric tons annually in 2005. The reaction described in this experiment illustrates the use of liquid bleach (11.5-12.5% available chlorine) as an oxidizing agent in the organic laboratory. 

Organic chemistry demands much from chlorine, both as an oxidizing agent and in substitution, since it often brings many desired properties in an organic compound when substituted for hydrogen, as in one form of synthetic rubber. 

Chlorine ttifluoride is commercially available at 99% minimum purity (108) and is shipped as a Hquid under its own vapor pressure in steel cylinders in quantities of 82 kg per cylinder or less. Chlorine ttifluoride is classified as an oxidizer and poison by DOT. 

Sulfur dioxide [7446-09-5] is formed as a result of sulfur oxidation, and hydrogen chloride is formed when chlorides from plastics compete with oxygen as an oxidant for hydrogen. Typically the sulfur is considered to react completely to form SO2, and the chlorine is treated as the preferred oxidant for hydrogen. In practice, however, significant fractions of sulfur do not oxidi2e completely, and at high temperatures some of the chlorine atoms may not form HCl. 

The iodides of the alkaU metals and those of the heavier alkaline earths are resistant to oxygen on heating, but most others can be roasted to oxide in air and oxygen. The vapors of the most volatile iodides, such as those of aluminum and titanium(II) actually bum in air. The iodides resemble the sulfides in this respect, with the important difference that the iodine is volatilized, not as an oxide, but as the free element, which can be recovered as such. Chlorine and bromine readily displace iodine from the iodides, converting them to the corresponding chlorides and bromides. 

The action of chlorine on ammonia can also be regarded as an oxidation reaction. 

Direct electrolysis was used at one time for the oxidation step. Manganese dioxide has also been used as an oxidant. Most present day processes use chlorine ... 

The formation of several oxidation states is typical of the elements on the right side of the periodic table. We have already discussed in Chapter 19 the fact that chlorine can exist in the + 1, +3, +5, and +7 oxidation states as well as in the — 1 state. In its compounds, chlorine is most often found in the — 1 state. This preponderance of — 1 compounds shows that elemental chlorine behaves as an oxidizing agent in most of its reactions. 

One other important compound of manganese is potassium permanganate, KMnO . This is an intensely violet-colored material much used as an oxidizing agent in the laboratory. (It is too expensive to use on a large scale in industry, chlorine is more likely to be used.)... 

Dipyridiue-chromium(VI) oxide2 was introduced as an oxidant for the conversion of acid-sensitive alcohols to carbonyl compounds by Poos, Arth, Beyler, and Sarett.3 The complex, dispersed in pyridine, smoothly converts secondary alcohols to ketones, but oxidations of primary alcohols to aldehydes are capricious.4 In 1968, Collins, Hess, and Frank found that anhydrous dipyridine-chromium(VI) oxide is moderately soluble in chlorinated hydrocarbons and chose dichloro-methane as the solvent.5 By this modification, primary and secondary alcohols were oxidized to aldehydes and ketones in yields of 87-98%. Subsequently Dauben, Lorber, and Fullerton showed that dichloro-methane solutions of the complex are also useful for accomplishing allylic oxidations.6... 

Removal as chlorine in an oxidation stage, mild enough to prevent any significant oxidation of easily oxidised organic matter. 

Is any substance identified as an oxidizer YES Oxygen feed chlorine gas intermediate... 

When chlorine is used as an oxidant, sodium bisulphite can be used for dechlorination. However, even after the process of dechlorination, free residual chlorine (FRC) may be present in the discharge. The sodium bisulphite used for dechlorination may also cause low levels of dissolved oxygen in the concentrate. For processes which use ozone, not only must it be removed to prevent damage to oxidant sensitive membranes, but also to prevent the formation of bromate, a known carcinogen, in waters containing bromide (Greenlee et al. 2009). 

ChemicaPPhysical Hwang et al. (2003) studied the chemical oxidation of mancozeb (100 ppm) in aqueous solution using ozone (continuously supplied at a concentration of 3 ppm) and chlorine dioxide (20 ppm). Ozonation of the solution for 60 min yielded several degradation compounds including ethylene thiourea as the major product. Degradation of mancozeb by chlorine dioxide also yielded ethylene thiourea. After 60 min of treatment, mancozeb was still detected suggesting that chlorine dioxide was less effective as an oxidant than ozone. However, the investigators... 

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