Ozonation yields

The following requirements will facilitate optimization of the ozone yield ... 

Alkenes with at least one vinjdic hydrogen undergo oxidative cleavage when treated with ozone, yielding aldehydes (Section 7.9). If the ozonolysis reaction is carried out on a cyclic alkene, a dicarbonyl compound results. 

The added value, variety of use, and methods to apply zeohte coatings or films in sensor apphcations has been convincingly demonstrated. Although current trends focus on miniaturization of sensors and creating smaUer zeohte crystals and thinner films, to decrease the response time of the sensor [79], often thick-film technology is sufficient to apply zeohte films for this type of application. Some sensor materials cannot withstand the high temperatures necessary for template removal by air calcination. Recent work demonstrated that ozonication yields... 

Harries showed that the degradation of rubber by ozone yielded chiefly levulinic acid and aldehyde (38). This fact, he concluded, indicated that rubber was made up of the repeating unit ... 

Photolytic. Coated glass fibers exposed to air containing 100-200 ppb ozone yielded... 

The primary ozonation by-products of atrazine (15 mg/L) in natural surface water and synthetic water were deethylatrazine, deisopropylatrazine, 2-chloro-4,6-diamino-s-triazine, a deisopropylatrazine amide (4-acetamido-4-amino-6-chloro-5-triazine), 2-amino-4-hydroxy-6-isopropylamino-5-triazine, and an unknown compound. The types of compounds formed were pH dependent. At high pH, low alkalinity, or in the presence of hydrogen peroxide, hydroxyl radicals formed from ozone yielded 5-triazine hydroxy analogs via hydrolysis of the Cl-Cl bond. At low pH and low alkalinity, which minimized the production of hydroxy radicals, dealkylated atrazine and an amide were the primary byproducts formed (Adams and Randtke, 1992). 

On the basis of deuterium labeling, 1,3-dipolar cycloaddition to the bridge C—C bond to form a cyclic trioxide was suggested. Rearrangements similar to those in alkene ozonation yield the products. 

The stoichiometric yield of OH0 is the greatest from the photolysis of hydrogen peroxide. But - as already mentioned - the photolysis of ozone yields more OH0 than that from hydrogen peroxide because of the higher molar extinction coefficient of ozone compared to hydrogen peroxide (see Table 2-3). 

Reference type of ww type of treatment system no, and type of ozone reactors (operating pressure) ozone production capacity nominal// real liquid flow-rate ozone yield coefficient Y(OJM) (M = COD) investment ozonation stage only specific costs (without annuity) remarks... 

Calculate parameters, e. g. ozone consumption rate r(03), ozone yield coefficient Y(03/ M) (see Table 1 -2). 

All experimental results should best be evaluated as a function of the specific ozone dose and related data such as the specific ozone absorption and/or consumption. Additionally the ozone yield coefficient, denoting the ratio of ozone absorbed in the liquid (i. e. transferred from the gas) to the DOC removed by ozonation or the total system (cf. Chapter B 1), is often of interest. 

Harries et al(Refs 2 3) claimed to prepare the diozonide and the diozonide peroxide of carvone. Their structures were not detd. The diozonide was obtained as a yel oil on treating carvone in CCl4 with ozone, followed by purification with pett ether. It deconpd on standing with formation of formaldehyde. Further treatment of diozonide with ozone yielded diozonide peroxide, which exploded by itself after standing for several hrs in a freezing mixt. It expld almost instantly when treated with warm w or when rubbed with a glass rod Refs l)Beil 7, 153, (101) [l28] 2)Beil 7,... 

Ozone Formation. Ozone is formed by the same mechanism as discussed in Part II. At constant flow rate and oxygen pressure of 0.25 atm. in a total pressure of 1 atm., the ozone yield was studied in... 

The structure of XXVI was deduced from the fact that it was different from the 2-cinnamylphenol obtained by direct C-cinnamylation of phenol.16 Later investigators showed that XXVI is the sole product ozonization yielded formaldehyde but not benzaldehyde. 7-Methyl-allyl phenyl ether also rearranges with inversion, yielding 2-(a-methyl-allyl)-phenol 36 the structure of the rearrangement product has been definitely established87 38 by a combination of degradative and synthetic procedures. 

There are two commercial processes for the production of peracetic acid (1) Low-temperature oxidation of acetaldehyde in the presence of metal salts, ultraviolet irradiation, or treatment with ozone yields acetaldehyde monoperacetate, which can be decomposed to peracetic acid and acetaldehyde. 

D-glucal, an acetyl group is removed from diacetyl-L-rhamnal by boiling its aqueous solution. The resulting monoacetyl-L-pseudorhamnal, however, is not as stable as diacetyl-D-pseudoglucal.7 Oxidation of diacetyl-L-rhamnal with ozone yielded 5-desoxy-L-arabinose, which was characterized as its phenylosazone and p-bromophenylosazone. 7 Deacetylation of diacetyl-L-rhamnal yields crystalline L-rhamnal (XLIV).7... 

The oxidation of hexaacetylmaltal with ozone yields 3-(a-D-gluco-pyranosyl)-D-arabinose hexaacetate, deacetylation of which leads to the free sugar itself (LXXVII).69... 

Oxidation, during the process of which there is no change in volume in so far as the ozone itself is concerned, each molecule of ozone yielding a molecule of oxygen, the third oxygen atom entering the oxidised product. This is the most usual type of oxidation. 

In acid solution, potassium bromide is oxidised quantitatively by ozone yielding an equimoleeular proportion of bromme,5 and this reagent can therefore be used for the estimation of dissolved ozone in the presence of hydrogen peroxide. ... 

Ferric hydroxide dissolves in potassium hydroxide in the presence of ozone, yielding potassium perferrate.1... 

Oxidation. Acetaldehyde is readily oxidized with oxygen or air to acetic acid, acetic anhydride, and peracetic acid (see Acetic acid AND DERIVATIVES). The principal product depends on the reaction conditions. Acetic acid [64-19-7] may be produced commercially by the liquid-phase oxidation of acetaldehyde at 65°C using cobalt or manganese acetate dissolved in acetic acid as a catalyst (34). Liquid-phase oxidation in the presence of mixed acetates of copper and cobalt yields acetic anhydride [108-24-7] (35). Peroxyacetic acid or a perester is believed to be the precursor in both syntheses. There are two commercial processes for the production of peracetic acid [79-21-0]. Low temperature oxidation of acetaldehyde in the presence of metal salts, ultraviolet irradiation, or ozone yields acetaldehyde monoperacetate, which can be decomposed to peracetic acid and acetaldehyde (36). Peracetic acid can also be formed directly by liquid-phase oxidation at 5 -50°C with a cobalt salt catalyst (37) (see Peroxides AND peroxy compounds). Nitric acid oxidation of acetaldehyde yields glyoxal [107-22-2] (38,39). Oxidations of -xylene to terephthalic acid [100-21-0] and of ethanol to acetic acid are activated by acetaldehyde (40,41). 

Both values are in excess of ozone yields actually achieved in ozonizers. If we assume that Reaction 9 proceeds at every termolecular collision, we can show that it will be faster than Reaction 2 as long as the ratio O/O2 1/100. 

At higher concentrations, ozone is more easily dissolved in the water and of course for a given water flow, less air need be compressed and dried. Unfortunately, as the concentration rises, the ozonizer yield drops. 

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