Short CommunicationNovel integrated electrodialysis/electro-oxidation process for the efficient degradation of 2,4-dichlorophenoxyacetic acid

- The novel combined cell improves mass transfer of single electrochemical oxidation.
- Removal rate of 2,4-D is double than a conventional electro-oxidation cell.
- Anionic membrane sorbs 2,4-D with a maximum capacity of 3.42 ± 0.24 mg cm−2.
- The degradation kinetics is more efficient in chloride media.

This work presents a novel approach of wastewater treatment technology that consists of a combined electrodialysis/electro-oxidation process, specially designed to allow increasing the efficiency in the oxidation of ionic organic pollutants contained in diluted waste. Respect to conventional electrolysis, the pollutant is simultaneously concentrated and oxidized, enhancing the performance of the cell due to the higher concentration achieved in the nearness of the anode. A proof of concept is tested with the ionic pesticide 2,4-D (2,4-dichlorophenoxyacetic acid) and results show that the efficiency of this new technology overcomes that electrolysis by more than double, regardless the supporting electrolyte used (either NaCl or Na2SO4). Moreover, the removal rate of 2,4-D when using NaCl was found to be more efficient, due to the best performance of the electrode material selected (DSA®) towards the formation of oxidants in chloride supporting electrolyte. These results open the way for overcoming the efficiency limitations of electrochemical treatment processes for the treatment of solutions with low concentrated ionic pollutants.

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