Degradation of nitrophenols by cathode reduction and Electro-Fenton methods

This study deals with the degradation of various nitrophenols by cathode reduction and Electro-Fenton methods. Using 4-NP as a model nitrophenol, the contribution of different reactions to the degradation of 4-NP is investigated. The degradation of 4-NP is much faster in the cathode cell than in the anodic cell. In the cathode cell, the degradation of 4-NP is significantly enhanced by the introduction of aeration and Fe2+. Treatment of high concentration of 4-NP in the undivided cell shows more than 98% removal of 4-NP and about 13% removal of TOC are obtained in both processes. Negligible quantity of nitrate and nitrite ions detected in both processes. Intermediates such as hydroquinone and bezoquinone are detected by GC/MS. The degradation pathway of 4-NP is proposed as the cathode reduction followed by hydroxyl oxidation.