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Abstract: It was investigated the feasibility of decolorization of an azo dye (DG 26) using a large scale nanotubular TiO2 structured electrode in a laboratory photoelectrochemical reactor (0.8L). Catalyst was grown by anodic oxidation directly on Ti surface and its microstructure and crystalline structure were characterized with SEM and XRD. TiO2/Ti photoactivity under different anodic polarization values was evaluated via photoelectrochemical tests. The nanostructured TiO2 was used in a reactor as photo-anode under UV monochromatic irradiation (254nm) and it was subjected to bias (+1.5V vs. SCE). A comparison with photolysis and photocatalysis processes was carried out under the same operating conditions to evaluate the synergistic action of photocatalysis and TiO2/Ti electrochemical polarization. Electrophotocatalysis was proven to be more effective than photocatalysis in DG 26 decolorization. Catalyst polarization resulted in synergistic effect on process yields. The complete decolorization of a 40mg/L solution of DG 26 was achieved in 24h, without adding chemical reagents, and catalyst durability was demonstrated over 360h tests. Therefore, the work done is challenging to prove that the process (irradiation+catalyst+polarization) is feasible and effectively up-grading to pilot and demonstrative scale applications after a fluid dynamics optimization of the photoreactor. [Copyright &y& Elsevier]