Effect of carbon material on the performance of a gas diffusion electrode in electro-fenton process

An enhancement of electro-Fenton treatment, performed by employing a PTFE-bonded gas diffusion cathode, is presented. The effect of different commercial carbon cloths on hydrogen peroxide production, iron regeneration and overall oxidation of an inorganic solution was investigated in electrolyses conducted under potentiostatic conditions. The influence of some operative conditions such as working potential, pH and feeding gas, is also reported. The results show that the hydrophilic nature of the coating highly improved the production of hydrogen peroxide, while iron regeneration is unaffected by the carbon characteristics only benefiting by less negative cathode potential and lower pH. Oxidation yields are confirmed to strictly depend on the concentration ratio of all the species involved. In particular, to limit the occurrence of undesired side reactions, excess of hydrogen peroxide has to be avoided.