불용성 전극의 Dye 제거 성능과 산화제 생성 비교

Abstract

The aim of this research was to evaluate the performance of insoluble electrode for the purpose of degradation of Rhodamine B (RhB) and oxidants generation [N,N-Dimethyl-4-nitrosoaniline (RNO, indicator of OH radical), <TEX>$O_3$</TEX>, <TEX>$H_2O_2$</TEX>, free Cl, <TEX>$ClO_2$</TEX>)]. Methods: Four kinds of electrodes were used for comparison: DSA (dimensional stable anode; Pt and JP202 electrode), Pb and boron doping diamond (BDD) electrode. The effect of applied current (0.5~2.5 A), electrolyte type (NaCl, KCl and <TEX>$Na_2SO_4$</TEX>) and electrolyte concentration (0.5~3.5 g/L) on the RNO degradation were evaluated. Experimental results showed that the order of RhB removal efficiency lie in: JP202 > Pb > BDD <TEX>${\fallingdotseq}$</TEX> > Pt. However, when concerned the electric power on maintaining current of 1 A during electrolysis reaction, the order of RhB removal efficiency was changed: JP202 > Pt <TEX>${\fallingdotseq}$</TEX> Pb > BDD. The total generated oxidants (<TEX>$H_2O_2$</TEX>, <TEX>$O_3$</TEX>, free Cl, <TEX>$ClO_2$</TEX>) concentration of 4 electrodes was Pt (6.04 mg/W) > JP202 (4.81 mg/W) > Pb (3.61 mg/W) > BDD (1.54 mg/W), respectively. JP202 electrode was the best electrode among 4 electrodes from the point of view of performance and energy consumption. Regardless of the type of electrode, RNO removal of NaCl and KCl (chlorine type electrolyte) were higher than that of the <TEX>$Na_2SO_4$</TEX> (sulfuric type electrolyte) RNO removal. Except BDD electrode, RhB degradation and creation tendency of oxidants such as <TEX>$H_2O_2$</TEX>, <TEX>$O_3$</TEX>, free Cl and <TEX>$ClO_2$</TEX>, found that do not match. RNO degradation tendency were considered a simple way to decide the method which is simple it will be able to determinate the electrode where the organic matter decomposition performance is superior. As the added NaCl concentration was increases, the of hydrogen peroxide and ozone concentration increases, and this was thought to increase the quantity of OH radical.