[Oxidative efficiency of the system of electrolysis coupled ozonation]

The oxidation system of electrolysis coupled ozonation (electrolysis-ozonation) was used to degrade 4-chlorophenol (4-CP), and its mechanism was discussed on the basis of kinetic analysis. The experimental results indicated the electrolysis-ozonation system had a significant synergistic effect during degradation of 4-CP. For example, the electrolysis-ozonation had the 4-CP removal rate of 92.7% and the COD removal rate of 64.9% in 900 s, respectively; while electrolysis alone plus ozonation alone only had the 4-CP removal rate of 69.7% and the COD removal rate of 30.1% under the same conditions. The results of H2O2 concentration analysis and photocurrent test showed that the synergistic mechanism of electrolysis-ozonation included two factors: (1) production of *03- at the cathode; (2) H2O2 generation resulting from reduction of dissolved oxygen. The above two factors led to generation of *OH in system effectively.