Oxygen ozone generator

Ozone Generation from Oxygen. Oxygen is dissociated iato atoms by iaelastic coUisions with energetic electrons (6—7 eV) (89,90). 

Ozone can be destroyed thermally, by electron impact, by reaction with oxygen atoms, and by reaction with electronically and vibrationaHy excited oxygen molecules (90). Rate constants for these reactions are given ia References 11 and 93. Processes involving ions such as 0/, 0/, 0 , 0 , and 0/ are of minor importance. The reaction O3 + 0( P) — 2 O2, is exothermic and can contribute significantly to heat evolution. Efftcientiy cooled ozone generators with typical short residence times (seconds) can operate near ambient temperature where thermal decomposition is small. 

Electronics Industry. Organic materials on the surface of electronic components are oxidized by immersion in deionized water that contains 0.5—2 ppm ozone residual. In some cases, gaseous ozone is employed to oxidize organic films on the surface of electronic components. In this treatment process, 5—6 wt % ozone, made in an oxygen-fed generator, is required. 

The mechanism for ozone generation is the exeitation and aeceleration of stray eleetrons within the high-voltage field. The alternating eurrent causes the electron to be attracted first to one electrode and then to the other. As the electrons attain sufficient velocity, they beeome capable of splitting some oxygen moleeules into free radical oxygen atoms. These atoms may then eombine with Oj moleeules to form O3. 

Atomic oxygen was generated by photolysis of ozone which passed through a quartz capillary tube (0 2 mm and lehgth 60 mm), using the 253.7 nm line from a low-pressure mercury lamp (LI). 

In air, in the absence of additives, NO removal takes place by oxidation [56-58], Wu et al. [56] observed that the concentration of ozone generated in the corona discharge in the presence of NO is significantly smaller as compared to the ozone formed in air without NO under the same conditions. Thus, they concluded that NO oxidation by ozone and atomic oxygen is an important reaction path for the NO conversion. 

The standard astm test method (D-1149-64) for rubber damage includes a test chamber (volume, 0.11-0.14 m ) through which ozonized air flows at a rate greater than 0.6 m/s. Because the residence time of the ozonized air in the test chamber is about 1 s, the ozone may be expected to reach the material in about 0.1 s. A somewhat similar test procedure (aatcc test method 109-1972 ansi L14, 174-1973) is used in testing colorfastness. The ozone generator is usually (but not necessarily) a mercury-vapor resonance lamp with emission lines at 184.9 and 253.7 nm. The 184.9-nm line is absorbed, and two ground-state oxygen atoms are produced ... 

It follows that, although the ozone concentration is more than 10,000 times that of the oxygen atom, the latter reacts so rapidly with olefins that oxygen atoms, rather than ozone, will be the species responsible for material damage, if the material is placed in the ozone generator. Similarly, for 02( d ) ... 

Economics. The manufacturer s retail price for the 66-lamp unit from Pure Water Systems, Inc. is 35,000. The cost of operation is based on energy usage, which is 1.5 KWH (manufacturer s estimate) if the current cost of electricity is 5 /KWH, then the daily operation would run 1.80/day or 657 annually. The cost of oxygen and the ozone generator are not included, nor do we have any estimate on long-term maintenance. 

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