Advanced oxidation effect of ozonation combined with electrolysis.
The advanced oxidation effect of ozonation combined with electrolysis (electrolysis-ozonation) was discussed through the treatment of 4-chlorobenzoic acid (4-CBA) as a hydroxyl radical probe. The mechanism of hydroxyl radical production by electrolysis-ozonation process was also estimated with a mathematical model. The experimental results revealed that the electrolysis-ozonation process had a synergistic effect on the degradation of 4-CBA. The advanced oxidation effect of electrolysis-ozonation was inferred from standard potentials of relevant electrochemical reactions and mathematical model analysis to be mainly attributed to ()O(3)(-) promotion of O(3) at the cathodes. An increase in electric current improved the degradation rate of 4-CBA. However, the pseudo-first order degradation rate constant reached a plateau at high electric current densities, as ()O(3)(-) promotion of O(3) at the cathodes was regulated by O(3) transport process from the bulk to the cathodes in the range exceeding an electric current density of 10 Am(-2). Accordingly, the balance of O(3) transport flux and electric current is important for the efficient operation of the electrolysis-ozonation reactor.
Kishimoto
Naoyuki
N
Faculty of Science and Technology, Ryukoku University, 1-5 Yokotani, Setaooe-cho, Otsu 520-2194, Japan. naoyuji@rins.ryukoku.ac.jp
Morita
Yukako
Y
Tsuno
Hiroshi
H
Oomura
Tomoaki
T
Mizutani
Hiroshi
H
D002723:Chlorobenzoates / Q000032:analysis; D004563:Electrochemistry; D004572:Electrolysis; D008956:Models, Chemical; D010084:Oxidation-Reduction; D010126:Ozone / Q000737:chemistry*; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000032:analysis*; D018508:Water Purification / Q000379:methods*
D002723:Chlorobenzoates; D014874:Water Pollutants, Chemical; D010126:Ozone; C040768:4-chlorobenzoic acid