| The electrochemical oxidation process is that refractory organic compounds are destructed by direct or indirect anodic oxidation. The electrochemical oxidation has attracted a great deal of attention, mainly because of their ease in operation, amenability to automation and its environmental compatibility.In this study, cyclic voltammetry and bulk electrolysis were used to investigate the effect of control factors on electrochemical oxidation of refractory organic compounds. The aniline and Acid Red B were used as model compounds.The results show that (1) The best condition of electrochemical oxidation of aniline is that aniline concentration is 508mg/L, current density 60mA/cm2, conductivity 1853 μs/cm;(2) The characteristic of electrochemical oxidation of Acid Red B has been studied by cyclic voltammetery. The voltammogram exhibits an oxidation peak at about -0.315V vs SCE, while a reduction peak appear at 0.289V vs SCE. The current densities are 12.65 mA/cm2 and -3.633mA/cm2 respectively;The reaction is irreversible because the AEp is large and ipa/ipc>l. (3) When the support electrolyte is Na2SO4, the removal ratios of Acid Red B and COD after 45 hours are 81.03% and 21.67% respectively;when the support electrolyte is NaCl, they are 90% and 30% after 10 minute respectively;but in electro-Fenton system, the removal ratio of Acid Red B reaches 98% after 10 minute. (4) The analysis of the UV-Vis spectra indicates that the electrochemical oxidation method could destroy not only azo bond but also unsaturated naphthyl conjugate system. The control factors are effective to increase the removal of the Acid Red B and COD. (5) In Na2SO4 and NaCl electrolytes system, the removal ratio of Acid Red B follows the pseudo-first order kinetics.The experimental results indicate that controlling the factors of solution can accelerate the reaction rate and increase the removals. The conclusions can also provide a reference for electrochemical oxidation technology and theory study.
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