Kinetics of electro-Fenton ferrous regeneration (EFFR) on chlorinated organic compound degradation

The electro-Fenton ferrous regeneration (EFFR) process was studied for kinetic determination under various reaction conditions. A novel model equation of this process was proposed which uses 2,4-dichlorophenol (2,4-DCP) as a chlorinated organic reference for this study. The operating parameters, pH, electrical current densities, and hydrogen peroxide concentrations, were varied to validate this novel model and kinetic rate constant estimation. The kinetic rate constant of the hydroxyl radical (·OH) with 2,4-DCP obtained by the novel model from this experiment was between 6.76 × 10 9 and 7.82 × 10 9  M −1 s −1. As a result, the novel model showed a more suitable fit with the experimental data than the first-order model method. The goodness of data fit which were indicated by correlation coefficients r 2 demonstrated that the novel model can better describe the kinetics of the process for chlorinated organic compound oxidation than the first-order model. Hydroquinone, maleic, acetic, formic, and oxalic acids were the main oxidation intermediates in this experiment. A degradation pathway for chlorinated organic compound oxidation by EFFR process was proposed on the basis of the intermediate compounds detected.