کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
6454251 | 1418811 | 2017 | 11 صفحه PDF | دانلود رایگان |
- A new electro-Fenton (EF) process using chalcopyrite as heterogeneous catalyst at neutral pH.
- Synergistic effect of Fe2+ and Cu2+ ions released by chalcopyrite.
- BDD anode is more efficient than Pt anode for tetracycline mineralization.
- EF/Chalcopyrite is more efficient than conventional EF process.
- Proposed oxidation pathway based on the identification of 19 intermediates.
The degradation of solutions of the antibiotic tetracycline (TC) has been studied by a novel electrochemical advanced oxidation process, consisting in electro-Fenton (EF) process using chalcopyrite as heterogeneous catalyst. In fact, chalcopyrite powder was the source of Fe2+ and Cu2+ ions instead of a soluble catalyst salt used in conventional EF. Experiments were performed in an undivided cell equipped with a Pt or boron-doped diamond (BDD) anode and a carbon felt cathode, where TC and its oxidation intermediate products were destroyed by hydroxyl radicals (OH) formed both, in the bulk solution from electrochemically induced Fenton's reaction (Fe2+ and H2O2) and Fenton's-like reaction (Cu+ and H2O2), and at the anode surface from water oxidation. The effects of operating parameters such as applied current, chalcopyrite concentration and anode material were investigated. TC decay followed pseudo-first-order reaction kinetics. The absolute rate constant for TC oxidation by OH was found to be 3.2Â ÃÂ 109Â Mâ1Â sâ1, as determined by the competition kinetic method. EF process using chalcopyrite as heterogeneous catalyst showed to be more efficient than conventional EF, achieving almost total mineralization of the TC solution (98% of total organic carbon removal) after 360Â min under optimum operating conditions. A plausible mineralization pathway for mineralization of TC aqueous solution by OH was proposed based on the identification of different oxidation by-products. Moreover, toxicity tests pointed out that this heterogeneous EF process was able to detoxify the TC solutions.
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Journal: Applied Catalysis B: Environmental - Volume 209, 15 July 2017, Pages 637-647