Ethylene with ozone

Unusually stable ozonides are prepared by treating mono- and bisffluroal-kyl)ethylenes with ozone [26] (equation 17)... 

Table 5.4. Reaction-Rate Constants of Substituted Ethylenes with Ozone ...

THE REACTIVITY OE ELUORO-AND CHLORO-SUBSTITUENTS OE ETHYLENE WITH OZONE QUANTUM-CHEMICAL CALCULATION... 

O ne. Air pollution (qv) levels are commonly estimated by determining ozone through its chemiluminescent reaction with ethylene. A relatively simple photoelectric device is used for rapid routine measurements. The device is caHbrated with ozone from an ozone generator, which in turn is caHbrated by the reaction of ozone with potassium iodide (308). Detection limits are 6—9 ppb with commercially available instmmentation (309). 

Chemiluminescence. Chemiluminescence (262—265) is the emission of light duting an exothermic chemical reaction, generaUy as fluorescence. It often occurs ia oxidation processes, and enzyme-mediated bioluminescence has important analytical appHcations (241,262). Chemiluminescence analysis is highly specific and can reach ppb detection limits with relatively simple iastmmentation. Nitric oxide has been so analyzed from reaction with ozone (266—268), and ozone can be detected by the emission at 585 nm from reaction with ethylene. 

Ozonuies (1,2,4-trioxolanes) are generally obtained by the reaction of fluoroalkenes with ozone Thus, vmyl fluonde is oxidized to monofluoroozomde and formyl fluonde [23] (equation 15) The same ozomde is formed by ozonolysis of a mixture of cis 1,2-difluoroethylene with ethylene [24]... 

Carbon monoxide and ethylene admitted into contact with ozone via an aluminium tip ignited and burned smoothly, while normal contact of carbon monoxide, nitrogen oxide, ammonia or phosphine causes immediate explosion at 0° or —78°C [1], At pressures below 10 mbar, contact with ethylene is explosive at —150°C [2], See Nitrogen oxide, below... 

The most widely used gas-phase chemiluminescence reagent is ozone. Analytically useful chemiluminescence signals are obtained in the reactions of ozone with NO, SO, and olefins such as ethylene and isoprene, but many other compounds also chemiluminesce with ozone. Ozone is conveniently generated online at mixing ratios of =1-5% by electrical discharge of air or 02 at atmospheric pressure [14]. 

FIGURE 6-10 Gas-phase (ozone-ethylene) chemiluminescent ozone monitor, block diagram. Reprinted with permission from ColofT et al. ... 

Photolytic. Photolysis products include carbon monoxide, ethylene, free radicals, and a polymer (Calvert and Pitts, 1966). Anticipated products from the reaction of acrolein with ozone or OH radicals in the atmosphere are glyoxal, formaldehyde, formic acid, and carbon dioxide (Cupitt,... 

Chemical/Physical. Gaseous products formed from the reaction of cyclohexene with ozone were (% yield) formic acid (12), carbon monoxide (18), carbon dioxide (42), ethylene (1), and valeraldehyde (17) (Hatakeyama et al., 1987). In a smog chamber experiment conducted in the dark at 25 °C, cyclohexane reacted with ozone. The following products and their respective molar yields were oxalic acid (6.16%), malonic acid (6.88%), succinic acid (0.63%), glutaric acid (5.89%), adipic acid (2.20%), 4-hydroxybutanal (2.60%), hydroxypentanoic acid (1.02%), hydroxyglutaric acid (2.33%), hydroxyadipic acid (1.19%), 4-oxobutanoic acid (6.90%), 4-oxopentanoic acid (4.52%), 6-oxohexanoic acid (4.16%), 1,4-butandial (0.53%), 1,5-pentanedial (0.44%), 1,6-hexanedial (1.64%), and pentanal (17.05%). 

Chemical/Physical. Gaseous products formed from the reaction of cyclopentene with ozone were (% yield) formic acid (11), carbon monoxide (35), carbon dioxide (42), ethylene (12), formaldehyde (13), and butanal (11). Particulate products identified include succinic acid, glutaraldehyde, 5-oxopentanoic acid, and glutaric acid (Hatakeyama et al., 1987). 

Some authors took advantage of the reactivity of polymers with ozone to recycle some peculiar plastic wastes coming from different origins. In this way, Fargere [155, 156] succeeded in degradation of cross-linked ethylene-vinyl acetate copolymers used in the production of sport shoes. This operation was achieved on grinded industrial wastes in suspension in CC14. In a second... 

Gehringer P, Proksch E, Eschweiler H, Szinovatz W. Remediation of groundwater polluted with chlorinated ethylenes by ozone-electron beam irradiation treatment. Appl Radiat Isot 1992 43 1107-1115. 

In [23], another reaction pathway was analyzed where ozone attacks ethylene with its central atom ... 

The limits, especially the upper limits, are slightly lower in smaller tubes due to the influence of the tube walls. The upper explosive limit of ethylene and air mixtures is raised from 16 per cent by volume of the hydrocarbon at 0 atmospheres pressure to 71 per cent at about 350 atmospheres pressure.32 It is probable that in the experiments with ozone to be described that the ozone acted as a trigger to set off the reaction which occurs with explosive violence when the proper mixtures of oxygen and ethylene are present.28... 

The action of ozone on acetylene is very violent and explosions result when the reaction is conducted in the vapor phase. However, it is possible to study the mechanism of the reaction by carrying out the ozonization in solution. The ozonide formed in this way is too unstable to be isolated and only by allowing a very slow decomposition to occur by slow evaporation of the solvent is it possible to isolate reaction products. In this way, it has been found that the material remaining after evaporation of the solvent consists of a large proportion of glyoxal (SI per cent) and a small amount of formic acid (5.6 per cent).1,12 The decomposition of the ozonide of acetylene differs from that of ethylene in that the linkage of carbon to carbon is not destroyed. The direct oxidation of acetylene with ozone, however, results in die formation oi formic acid and carbon dioxide.188... 

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