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HYDROGEN PEROXIDE GENERATION AND CAPILLARY ELECTROPHORESIS FOR ELECTRO-FENTON OXIDATION

J. Environ. Eng. Manage 01/2009; 19:307-314.

ABSTRACT Optimum conditions for generating hydrogen peroxide in Electro-Fenton oxidation in an undivided cell at a carbon cloth cathode were individuated, examining the effect of cathode potential, technique for providing oxygen, pH and concentration of electrolyte. The best conditions are: cathode potential -1 V vs. Ag/AgCl, air sparing 1 L min -1 at the cathode, pH 3.0 in 0.05 M sodium sulphate electrolyte. Capillary electrophoresis was investigated as a potential analytical technique for monitoring electro-Fenton oxidation of chlorinated anilines by determining the inorganic ions produced. The sequential analysis of the six ionic species investigated required less than 1 h on a routine basis. In the electro-Fenton oxidation of chloroanilines, stoichiometric amounts of ammonium and chloride ions were measured after 180-min treatment; no nitrite or nitrate ions were detected. Fe 2+ was continuously regenerated at the cathode and the observed time trends of Fe 2+ and Fe 3+ concentrations showed marked differences in the presence or absence of chloroanilines.

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