Oxidation of chlorite

Jayne JE (1953) A study of the alkaline nitrobenzene oxidation of chlorite lignin Tappi 36 571-576... 

Oxidation of chlorite has a higher rate coefficient at 25 °C than that of chloride, but obeys the same rate equation (3) and is believed to have the same fundamental mechanism. 

Similar to this is the oxidation of chlorite to chlorine dioxide with nitrogen trichloride (19). In the laboratory, the passage of air-diluted chlorine gas... 

Bain, D. C., 1972. Oxidation of chlorites in soil clays and effect on DTA curves. Nature Phys. Sci. 238 142. 

Chlorite ion is oxidized rapidly to chlorine dioxide by ozone at pH 4, yielding one mol CIO2 per mol O3 when chlorite is in excess (k > lO" (39). The oxidation of bromite to bromate by ozone is too rapid to measure. Chlorine dioxide is oxidized rapidly to chlorate. Chlorate, bromate, and iodate ions do not react with ozone. 

HCIO4, one of the strongest of the mineral acids. The perchlorates are more stable than the other chlorine oxyanions, ie, chlorates, CIO chlorites, CIO or hypochlorites, OCf (3) (see Chlorine oxygen acids and salts). Essentially, all of the commercial perchlorate compounds are prepared either direcdy or indirectly by electrochemical oxidation of chlorine compounds (4—8) (see Alkali and chlorine products Electrochemical processing). 

Oxidation. Oxidation of the -amyl alcohols produces aldehydes, which after continued oxidation can yield acids. This route to aldehydes has httle merit. However, oxidative esterifications with alkah metal hypohaUtes (eg, calcium chlorite, Ca(OCl)2) (49), bromates (eg, sodium bromate, NaBrO )... 

Sodium chlorite oxidation of com and rice starches is recommended for the production of textile sizes (101) and oxidized starch is recommended as a hardening agent in the immobilization of microbial cells within gelatin (102). 

The pH of the chlorine dioxide reaction mixture must be maintained in the 2.8—3.2 pH range, otherwise decreased conversion yields of chlorite to chlorine dioxide are obtained with by-product formation of chlorate. Generator efficiencies of 93% and higher have been demonstrated. A disadvantage of this system is the limited storage life of the sodium hypochlorite oxidant solution. 

Electrochemical Generation of Chlorine Dioxide from Chlorite. The electrochemical oxidation of sodium chlorite is an old, but not weU-known method of generating chlorine dioxide. Concentrated aqueous sodium chlorite, with or without added conductive salts, is oxidized at the anode of an electrolytic cell having a porous diaphragm-type separator between the anode and cathode compartments (122—127). The anodic reaction is... 

Hypophosphoric acid, (H0)2P(0)-P(0)(0H)2, is usually prepared by the controlled oxidation of red P with sodium chlorite solution at room temperature the tetrasodium salt, Na4P2O6.10H2O, crystallizes at pH 10 and the disodium salt at pH 5.2 ... 

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) ... 

If the reagent that is added does not remain in the initial form in the reaction mixture, the investigator must carefully identify the actual species present. For example, the oxidation of iodide ions by chlorite ions in acidic solution has a rate given by... 

OXIDATION OF PRIMARY ALCOHOLS TO CARBOXYLIC ACIDS WITH SODIUM CHLORITE CATALYZED BY TEMPO AND BLEACH 4-METHOXYPHENYLACETIC ACID... 

The effect of silver chlorite on iodomethane in the absence of any solvent gives rise to an immediate explosion. During another attempt it was observed that the presence of a solvent delays but does not prevent the explosion from happening. This accident can be intapreted in two different ways instability of the methyl chlorite formed, or violent oxidation of the iodised compound by silver chlorite, which is a strong oxidant. 

Barium chlorite had been added to dimethyl sulphate. The mixture combusted immediately. This behaviour was explained by the formation of methyl chlorite. This accident can also be explained by an oxidation of sulphate by chlorite, whose exothermicity would have caused the compound s self-ignition. The author believes that the instability of methyl chlorite would give rise to a violent detonation rather than an ignition. 

The Fe +/Mg and Fe- /Fe values of chlorite from Kuroko deposits and Neogene Cu-Pb-Zn vein-type deposits differ greatly (Fig. 1.83). Chlorite from Kuroko deposits contains lower Fe +/Mg and higher Fe /Fe " " values than this from the Neogene vein-type deposits in Japan. The most likely explanation for these differences is that these two types of deposit formed at different states of oxidation, although other... 

One feature of this oxidation system is that it can selectively oxidize primary alcohols in preference to secondary alcohols, as illustrated by Entry 2 in Scheme 12.5. The reagent can also be used to oxidize primary alcohols to carboxylic acids by a subsequent oxidation with sodium chlorite.34 Entry 3 shows the selective oxidation of a primary alcohol in a carbohydrate to a carboxylic acid without affecting the secondary alcohol group. Entry 5 is a large-scale preparation that uses NaC102 in conjunction with bleach as the stoichiometric oxidant. 

Sodium chlorite reacts very violently with organic compounds of divalent sulfur, or with free sulfur (which may ignite), even in presence of water. Contact of the chlorite with rubber vulcanised with sulfur or a divalent sulfur compound should therefore be avoided [1]. Application of factorial design techniques to experimental planning gave specific conditions for the safe oxidation of organic sulfides to sulfoxides using sodium chlorite or calcium hypochlorite [2],... 

Oxidation of the tetrahydroindolizine 338 with sodium chlorite gives the lactam 339, which rapidly lactonizes to give the pyranoindolizine 340 (Equation 122) <2001T8647>, and the one-pot , three-component reaction between the keto ester 235, acrolein, and o-aminophenol (formally analogous to that of Equation 63) gives the benzoxazolo-naphthyridine 341 (Equation 123) <20010L2145>. 

Oxides of chlorine are both more numerous and more useful than those of fluorine. These oxides are the anhydrides of several important acids, and the oxyanions of those acids constitute the hypochlorites, chlorites, chlorates, and perchlorates. The first oxide of chlorine, C120 (m.p. -20 °C, b.p. +2 °C), contains chlorine in the +1 oxidation state. It can be prepared by the reaction... 

The immunological properties of a modified S14, obtained on treatment with D-galactose oxidase and subsequent oxidation of the aldehyde group to a carboxyl group with chlorite, have been investigated.45... 

Moderately difficult floating ores - cassiterite sulphide deposits with small quantities of chloritic tourmaline and Fe-oxides are considered to be moderately difficult. 

The Olin Corporation has developed an electrochemical chlorine dioxide generator technology that safely and conveniently produces aqueous chlorine free solutions of chlorine dioxide at chlorite molar conversion efficiencies of 95% or better [221-224]. The chlorine dioxide is produced by direct oxidation of sodium chlorite, Fig. 21. The electrochemical C102 generator system is shown in Fig. 22. 

Selective oxidation of dimethylanisoles (11,441). An o- or a p-methyl group in a dimethylanisole that bears an m-methyl group is selectively oxidized by K2S208 catalyzed by CuS04 to an aldehyde group, which can be oxidized further to a carboxyl group by sodium chlorite.1... 

Many of the salts which have been prepared are explosive and sensitive to heat or impact. These include chlorites of copper (violent on impact), hydrazine (monochlorite, inflames when dry), nickel (explodes at 100°C but not on impact), silver (at 105° or on impact), sodium, tetramethylammonium, mercury, thallium and lead (which shows detonator properties). Several other chlorites not isolated and unstable in solution include mono-, di- and tri-methylammonium chlorites. The metal salts are powerful oxidants [1], Chlorites are much less stable than the corresponding chlorates, and most will explode under shock or on heating to around 100°C [2], Individually indexed compounds are ... 

The oxidation of formaldehyde by chlorite, C102, has been studied in aqueous solution.In the presence of excess chlorite, formaldehyde was oxidized to CO2, with CIO2 also being formed. This compound was also obtained as an oxidation product when HCHO was in excess, in which case the latter was oxidized only as far as formic acid. The first step of the reaction produces HOCl, which acts as an autocatalyst, catalysing the formation of CIO2 and the further oxidation of HCO2H to CO2. The build-up of CIO2 is due to the fact that HOCl reacts much more rapidly... 

Oxidizers may not themselves be combustible, but they may provide reaction pathways to accelerate the oxidation of other combustible materials. Combustible solids and liquids should be segregated from oxidizers. Certain oxidizers undergo dangerous reactions with specific noncombustible materials. Some oxidizers, such as calcium hypochlorite, decompose upon heating or contamination and self-react with violent heat output. Oxidizers include nitrates, nitric acid, nitrites, inorganic peroxides, chlorates, chlorites, dichromates, hypochlorites, perchlorates, permanganates, persulfates and the halogens. 

Effective conditions for oxidation of aldehydes to carboxylic acids with KMn04 involve use of t-butanol and an aqueous NaH2PC>4 buffer as the reaction medium.173 Buffered sodium chlorite is also a convenient oxidant.174 175 An older reagent for carrying out the aldehyde — carboxylic acid oxidation is silver oxide. 

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