Chlorine -oxide

Several chlorine oxides are known, and they are the anhydrides of the chlorine oxyacids. One of them, C102, has several important uses on an industrial scale. Dichlorine monoxide, C120, is an explosive gas (m.p. -116 °C, b.p. +2 °C) that is obtained as a product of the following reaction  

This oxide is very soluble in water, and it is the anhydride of HOC1  

This reaction illustrates the major use of C120. The C120 molecule has a bent (C2v) structure with a Cl-O-Cl angle of 110.8°. It reacts with N2Os to give chlorine nitrate, C1N03  

The other products in Eq. (16.73) depend on the reaction conditions. In the CINO3 molecule the chlorine atom is bonded to oxygen so the linkage is C10N02. Dichlorine 

Chlorine dioxide, C102, is an explosive gas (m.p. -60 °C, b.p. 11 °C) that has been used as a dry, gaseous bleach. It has a bent (C2v) structure with an 0-C1-0 angle of 118°. Although C102 has an odd number of electrons, it does not dimerize. The reaction, 

The flash photolysis study of Norrish et al,415 has confirmed the suggestions of earlier workers that CIO is an important reaction intermediate. It reaches its maximum concentration during the photolytic flash and is clearly generated in 

The decay of CIO subsequent to the flash is bimolecular, and the rate coefficient for 

The larger quantum yield of 4.5 observed424 for wavelengths between 2350 and 2750 A is possibly an indication of a contribution from (6a) to the primary process in this region, as is also suggested by the absorption spectrum414 42S. The extent to which the rather unlikely414 dissociation process 

A quantum yield I ci2o 1-8 has been reported426 for the photolysis at 4358 A of C120 in CC14 solution. C102 is an important product of the photolysis in 

C10 + C102 C1203 CIO + ci2o3 -+ ClOOCl+cio2 Propagation  

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Diehlorine heptoxide, CI2O,. M.p. —91-5 C, b.p. 82"C, the most stable chlorine oxide but still explosive (HCIO4 plus P2OS), gives HCIO4 with water. 

Fluorene can be nitrated, sulphonated and chlorinated. Oxidation gives fluorenone (9 O). 

Dichlorine h ptoxide, CljO, is the most stable of the chlorine oxides. It is a yellow oil at room temperature, b.p. 353 K, which will explode on heating or when subjected to shock. It is the anhydride of chloric(VlI) acid (perchloric acid) from which it is prepared by dehydration using phosphorus(V) oxide, the acid being slowly reformed when water is added. 

Hquid and gaseous reactants, Hquid products benzene chlorination, oxidation 0.01-0.2 1-30 100-500 100-500... 

Cla.riGers. Pool water may occasionally contain metallic impurities such as copper, iron, or manganese which enter the pool with the makeup water or by corrosion of metallic parts in the circulation system. These dissolved metals can discolor the water and cause stains. Chlorine oxidizes soluble Fe and to the highly insoluble Fe(OH)3 and MnO which can be removed by filtration. Water-soluble, high molecular weight polymers can be... 

Anhydride of chloric acid, Cl20, is unknown. Oxides with even number of oxygen atoms are mixed anhydrides. Other chlorine oxides such as the radicals CIO, CIO, and CIO are known. Chlorine monoxide [14989-30-17, CIO, plays a key role in depletion of the o2one layer. 

The chlorine oxides are anhydrides or mixed anhydrides of the chlorine oxo-acids oxides with an odd number of oxygens are simple anhydrides whereas those with an even number are mixed anhydrides. 

Dichlorine monoxide is the anhydride of hypochlorous acid the two nonpolar compounds are readily interconvertible in the gas or aqueous phases via the equilibrium CI2 O + H2 0 2H0Cl. Like other chlorine oxides, CI2O has an endothermic heat of formation and is thus thermodynamically unstable with respect to decomposition into chlorine and oxygen. Dichlorine monoxide typifies the chlorine oxides as a highly reactive and explosive compound with strong oxidhing properties. Nevertheless, it can be handled safely with proper precautions. 

Aqueous chlorine oxidizes numerous inorganic substrates. However, since HOCl and C10 coexist over a wide pH range, kinetic studies are necessary to estabHsh their respective roles both species are seldom active in the same reaction (97). The oxidation of CN is an important reaction in the treatment of waste-water and proceeds by the intermediate CICN (98). 

Thermal Decomposition of GIO2. Chloiine dioxide decomposition in the gas phase is chaiacteiized by a slow induction period followed by a rapid autocatalytic phase that may be explosive if the initial concentration is above a partial pressure of 10.1 kPa (76 mm Hg) (27). Mechanistic investigations indicate that the intermediates formed include the unstable chlorine oxide, CI2O2. The presence of water vapor tends to extend the duration of the induction period, presumably by reaction with this intermediate. When water vapor concentration and temperature are both high, the decomposition of chlorine dioxide can proceed smoothly rather than explosively. Apparently under these conditions, all decomposition takes place in the induction period, and water vapor inhibits the autocatalytic phase altogether. The products of chlorine dioxide decomposition in the gas phase include chlorine, oxygen, HCl, HCIO, and HCIO. The ratios of products formed during decomposition depend on the concentration of water vapor and temperature (27). 

Chlorination/oxidation of cyanide wastes from heat treatment plant Mixing cyanide with acids liberates hydrogen cyanide Hydrogen cyanide... 

Cyanides are dangerously toxic materials that can cause instantaneous death. They occur in a number of industrial situations but are commonly associated with plating operations, and sludges and baths from such sources. Cyanide is extremely soluble and many cyanide compounds, when mixed with acid, release deadly hydrogen cyanide gas. Cyanide is sometimes formed during the combustion of various nitrile, cyanohydrin, and methacrylate compounds. Cyanides (CN ) are commonly treated by chlorine oxidation to the less toxic cyanate (CNO ) form, then acid hydrolyzed to COj and N. Obviously, care should be taken that the cyanide oxidation is complete prior to acid hydrolysis of the cyanate. 

The commercial recovery of iodine on an industrial scale depends on the particular source of the element.Erom natural brines, such as those at Midland (Michigan) or in Russia or Japan, chlorine oxidation followed by air blowout as for bromine (above) is much used, the final purification being by resublimation. Alternatively the brine, after clarification, can be treated with just sufficient AgNOs to precipitate the Agl which is then treated with clean scrap iron or steel to form metallic Ag and a solution of EeU the Ag is redissolved in HNO3 for recycling and the solution is treated with CI2 to liberate the h ... 

Figure 17.16 Molecular structure and dimensions of gaseous molecules of chlorine oxides as determined by microwave spectroscopy (CI2O and CIO2) or electron diffraction (CI2O7).

Chlorine oxidation of sodium chlorite has also been used on both an industrial scale (by mixing concentrated aqueous solutions) or on a laboratory scale (by passing CVair through a column packed with the solid chlorite) ... 

The structures of the chlorine oxide fluorides are summarized in Fig. 17.26, together with those of related cationic and anionic species formed from the neutral molecules by gain or loss or F . The first conclusive evidence for free FCIO in the gas phase came in 1972 during a study of the hydrolysis of CIF3 with substoichiometric amounts of H2O in a flow reactor ... 

Figure 17.26 Structures of chlorine oxide fluorides and related cations and anions.

Despite several attempts at synthesis, there is little or no evidence for the existence of FBrO, p3Br02 or FsBrO. The bromine oxide fluorides are somewhat less thermally stable than their chlorine analogues and somewhat more reactive chemically. The structures are as already described for the chlorine oxide fluorides (Fig. 17.26). 

Chlor-oxyd, n. chlorine oxide, -phosphor, m. phosphorus chloride, -pikrin, n. chloropicrin. -platin, n. platinic chloride, -platinsiiure,. chloroplatinic acid, -quecksilber, n. mercury chloride (either one), -raucherung, /. chlorine fumigation. 

In the solvent-extraction process, the platinum metal concentrate is solubilized in acid using chlorine oxidant. Ruthenium and osmium are separated by turning them into the volatile tetroxides. 

Where soluble iron is present in condensate, it often is associated with copper. When the problem is considered serious, it usually is removed by a condensate polisher. Soluble iron in MU often is associated with manganese and usually (but not totally) is removed either by ion-exchange resins (often inadvertently) or in an aeration tower, where the process employs a combination of air or chlorine oxidation, followed by precipitation and filtration. 

A study of the chlorine oxidation of 2-hydroxyethyl octyl sulphoxide92 (equation 28) showed that a cyclic intermediate is probably involved in the process which gives the sulphone in good yield. Labelling studies have shown that the hydroxyl group is replaced by a chlorine atom whilst the hydroxyl oxygen atom is transferred to the sulphur atom. A similar result was obtained for 3-hydroxypropyl and 4-hydroxybutyl alkyl sulphoxides93. 

Susan Solomon and James Anderson showed that CFCs produce chlorine atoms and chlorine oxide under the conditions of the ozone layer and identified the CFCs emanating from everyday objects, such as cans of hair spray, refrigerators, and air conditioners, as the primary culprits in the destruction of stratospheric ozone. The CFC molecules are not very polar, and so they do not dissolve in rain or the oceans. Instead, they rise to the stratosphere, where they are exposed to ultraviolet radiation from the Sun. They readily dissociate in the presence of this radiation and form chlorine atoms, which destroy ozone by various mechanisms, one of which is... 

Treatment with chlorine gas converts amines to chloramines, whose active chlorine oxidizes iodide to iodine. This then forms the well-known, deep blue iodine-starch complex [13]. 

Neutrophils Contain Myeloperoxidase, Which Catalyzes the Production of Chlorinated Oxidants... 

The oxidation by Mn(lII) chloride involves three complexes and the kinetic data of Taube " are summarised in Table 15. The greater thermal stability of the /m-complex is considered to result from the lowering of the free energy relative to the transition state as compared with bis- and mono-complexes. The study of MnC204 was based on the Mn(III)-catalysed chlorine oxidation of oxalic acid. ... 

It is necessary therefore to seek the cause of the induced air oxidation in the ClOJ-Cl system. The fact that, during the stepwise reduction of chlorate, chlorine oxide (CIO), which can easily react with molecular oxygen ... 

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