Electrolyzed oxidizing water

Walker, S. P., Demirci, A., Graves, R. E., Spencer, S. B., and Roberts, R. F. (2005a). Cleaning milking systems using electrolyzed oxidizing water. Trans. ASAE 48,1827-1833. 

Guentzel, J. L., Liang Lam, K., Callan, M. A., Emmons, S. A., and Dunham, V. L. (2008). Reduction of bacteria on spinach, lettuce, and surfaces in food service areas using neutral electrolyzed oxidizing water. Food Microbiol. 25,36-41. 

Shimizu, Y. and Sugawara, H. (1996) Virucidal and bactericidal effects of electrolyzed oxidizing water and hypochlorous add. Jpn. J. Oral Biol. 38, 564-571. 

Stevenson, S. M. L., Cook, S. R., Bach, S. J., and McAllister, T. A. (2004). Effects of water source, dilution, storage, and bacterial and fecal loads on the efficacy of electrolyzed oxidizing water for the control of Escherichia coli 0157 H7. /. Food Prot. 67,1377-1383. 

S.-Y. Hsu and H.-Y. Kao. Effects of storage conditions on chemical and physical properties of electrolyzed oxidizing water. Journal of Food Engineering 65 465 71, 2004. 

Shirahata S, Kabayama S, Nakano M, Miura T, Kusumoto K, Gotoh M, Hayashi H, Otsubo K, Morisawa S, Katakura Y. Electrolyzed-reduced water scavenges active oxygen species and protects DNA from oxidative damage. Biochem Biophys Res Commun 1997 234 269-74. 

If F2 were formed by the electrolysis of an aqueous fluoride solution, it would immediately oxidize water to oxygen. For this reason, fluorine is prepared by electrolyzing liquid hydrogen fluoride containing potassium fluoride to increase its conductivity, at about 70°C (Figure 21.17) ... 

Electrolysis of Water and Nonstandard Half-Cell Potentials Before we can analyze the electrolysis products of aqueous salt solutions, we must examine the electrolysis of water itself. Extremely pure water is difficult to electrolyze because very few ions are present to conduct a current. If we add a small amount of a salt that cannot be electrolyzed in water (such as Na2S04), however, electrolysis proceeds rapidly. A glass electrolytic cell with separated gas compartments is used to keep the H2 and O2 gases from mixing (Figure 21.25). At the anode, water is oxidized as the O.N. of O changes from —2 to 0 ... 

The reduction half-reaction is an easy two-electron transfer reaction, while four electrons are involved in the oxidation of water to form oxygen. While by no means trivial, it is considerably easier to photo-oxidize water than it is to photoreduce CO2. Moreover, hydrogen can be readily converted into electricity - and back again - with fuel cells and electrolyzers. This offers the prospect of a future energy infrastructure based oti sunlight, hydrogen, and electricity, as illustrated in Fig. 1.2. 

Fig. 23.9. Legionella inactivation with tap water with added sodium hypochlorite and electrolyzed tap water (A) 0.18 ppm oxidant as CI2 (tap water + NaOCl). and ( ) 0.19 ppm oxidant as CI2 (tap water -150 mA cm 2).

Tables 23.3 and 23.4 show Legionella inactivation with electrolyzed DI water and electrolyzed tap water, both containing injected sodium chloride. Comparing these data, the inactivation behavior was similar, despite chloride concentrations that differed by more than a factor of two. With a comparison at a current density of 50 mA cm the oxidant levels were also differed by more than a factor of two. This suggests that not only hypochlorite is active but also one or more other disinfectants are generated in tap water electrolysis. 

Peroxide from carbonate is the most powerful disinfectant in electrolyzed tap water. Bicarbonates definitely have many advantages, as there is no hypochlorite production, i.e., no chlorine-related drawbacks, and small total oxidant production is sufficient for good inactivation, even at small current densities. Since bicarbonates are always present in tap water, tap water electrolysis can also result in good Legionella inactivation. 

When carrying out an electrolysis in solution, we must consider the possibility that other species present might be oxidized or reduced by the electric current. For example, suppose that we want to electrolyze water to produce hydrogen and oxygen. Because pure water does not carry a current, we must add an ionic solute with ions that are less easily oxidized or reduced than water ... 

In this method, each gas is produced in a separate compartment so they have high purity. In this process, deuterium oxide, D20, is electrolyzed more slowly so the water becomes enriched in the heavier isotope. The other electrolytic process that produces hydrogen is the electrolysis of a solution of sodium chloride. 

When water is electrolyzed with copper electrodes or using other common metals, the amount of 02(g) is less than when Pt electrodes are used, but the amount of H2(g) produced is independent of electrode material. Why does this happen In electrolysis, the most easily oxidized species is oxidized and the most easily reduced species is reduced. If we compare Cu and H20 by looking on the standard reduction potentials chart (data given below), we see that Cu is a stronger reducing agent than H20, because 0.337 V is less than 0.828 V. This means that Cu is more easily oxidized than water. 

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