Ozone reactive substance

Phenols. The first stable ozone oxidation product of phenol in water is ds ds-raucomc acid, which requires - 2 mol O /mol phenol. In practice, larger dosage levels of ozone are required because other ozone-reactive substances are present in most wastes. Ozone oxidation of phenoHc effluents is employed in paper mills, coke mills, oil refineries, and thermoplastic resin manufacture, producing effluents that are safe to freshwater biota (122,123) (see Lignin Pulp). 

Ozone is considered a reactive substance against plastics due to its ability to readily degrade into an atom and a molecule of oxygen. The atomic oxygen... 

The reactive species, called ozone-depleting substances, come from different source gases such as H2, H2O, N2O and CH4 - halogenated organic compounds). Noteworthy that influencing the stratosphere with water (from aircrafts) and hydrogen (H2 technology in discussion) results in ozone depletion. An important source of H2O is methane, and a H2O concentration maximum found between 50 and 70 km altitude results in CH4 oxidation ... 

Like DPD, indigo trisulphonate is not a specific reagent to ozone. How ever, it is only decolourized by such reactive oxidation agents as chlorine, chlorine dioxide and ozone. Other substances contained in the water, such as chlorite, chlorate and hydrogen peroxide do not interfere. Chlorine can be masked by adding malonic acid. 

For each type of component, its relative reactivity in ozone formation was taken into account which makes it possible to characterize by weighting the behavior of the overall motor fuel under the given experimental conditions. The overall reactivity is in fact governed by a limited number of substances ethylene, isobutene, butadiene, toluene, xylenes, formaldehyde, and acetaldehyde. The fuels of most interest for reducing ozone formation are those which contribute towards minimizing emissions of the above substances. 

Ozone can be analyzed by titrimetry, direct and colorimetric spectrometry, amperometry, oxidation—reduction potential (ORP), chemiluminescence, calorimetry, thermal conductivity, and isothermal pressure change on decomposition. The last three methods ate not frequently employed. Proper measurement of ozone in water requites an awareness of its reactivity, instabiUty, volatility, and the potential effect of interfering substances. To eliminate interferences, ozone sometimes is sparged out of solution by using an inert gas for analysis in the gas phase or on reabsorption in a clean solution. Historically, the most common analytical procedure has been the iodometric method in which gaseous ozone is absorbed by aqueous KI. 

An appreciable body of evidence has accumulated to indicate that ozone has extrapulmonary effects. Although some of the reported effects may be secondary to the reaction of ozone with intrapulmonary neural receptors or to release of humoral substances from the lung, other finding appear to be mote directly related to an oxidizing effect of ozone. The biochemical basis for the latter is unclear, particularly because the reactivity of ozone and its short-lived intermediates would make it unlikely for them to penetrate the pulmonary parenchyma. Earlier studies on the subject of extrapulmonary effects have been reviewed by Stokinger. ... 

The solvent should not contain substances that contribute significantly to the production of photochemical smog and troposphere ozone. The volatile organic content of the product, as used, should not exceed 50 g/L. None of the components of the product will have a maximum incremental reactivity (MIR) exceeding 1.9 g Ofg of compound (the MIR for toluene). MIR values can be obtained from the maximum incremental reactivity list found in Appendix VII of the California Air Resources Board s California Exhaust Emission Standards and Test Procedures for 1988 and Subsequent Model Passenger Cars, Light-Duty Trucks and Medium-Duty Vehicles as amended on September 22, 1993. 

Exercise 22-39 What products would you expect to be formed in the ozonization of the following substances Consider carefully which bonds are likely to be most reactive. 

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