Abstract：The present study investigated the integrated treatment of Tl-containing wastewater by electrooxidation-electrocoagulation (EO-EC) based on a dimensionally stable RuO2-IrO2/Ti electrode and a sacrificial Fe0 electrode compared with the single electrocoagulation (EC). Further, the mechanism of Tl removal by EO-EC was discussed. In contrast to the single EC, the EO-EC(1:1) was suitable for the advanced treatment of Tl-containing wastewater in a wide pH (4~10) and current density (5~20mA/cm2) range and was less prone to passivation. Active chlorine and the ORP (oxidation-reduction potential) played a vital role in the indirect oxidation of Tl(I) to Tl(III) by EO-EC. The floc analyses showed that Tl(OH)3(s) was co-precipitated with Fe(OH)3(am), and the residual Tl(I) was adsorbed on the lepidocrocite. This study offered an integrated EO-EC method for remediation of Tl-containing wastewater, which can meet the discharge standard of <2µg/L for Tl is economically feasible.
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