This work assesses the role of the operational conditions upon the electro-activation of persulfate (electro-PS) using Ti/IrO2-Ta2O5 electrode for the decolorization of anthraquinone azo dye Disperse Blue 3 (DB3). The studied variables include current density (j) (5-80 mA cm(-2)), persulfate concentration based on the stoichiometric dose for complete DB3 mineralization (20-100%), temperature (30-90 degrees C) and pH (3-12) as well as the influence of dissolved oxygen. The persulfate activation from cathodic reduction was confirmed by linear sweep voltammetry (LSV). The increase in j enhanced the PS decomposition and, consequently, decolorization efficiency, because of the greater production of sulfate radicals (SO4 center dot-). Besides, the combination of electro-PS with thermal activation resulted in a synergistic effect upon the DB3 mineralization. In the range 30-70 degrees C, electro-PS led to a significantly higher TOC conversion (above 60% at 40 mA cm(-2)) than sole heat-activated PS. This difference steeply decreased as temperature increases, achieving similar TOC conversion at 90 degrees C after 60 min. (C) 2017 Elsevier Ltd. All rights reserved.