Electrochemical oxidation of synthetic solutions of phenol, 2-chlorophenol, 2-6 di chlorophenol was investigated at different experimental conditions. Carbon materials, like carbon felt or reticulated vitreous carbon (RVC), as well as titanium plates coated with PbO₂ or SnO₂ were respectively used as three and bi-dimensional electrodes. Two electrochemical cell configurations (flow-by and flow- through) were used for the electrolyses. Experiments were extended to oxidation of a real waste contituted by an old landfill leachate in order to verify the possibility to further reduce the organic load due to the presence of biorefractory substances and the ammonium nitrogen in it contained.