Electro‐Fenton Treatment of Photographic Processing Wastewater |
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| Authors: | Nasr Bensalah Ahmed Bedoui Shankararaman Chellam Ahmed Abdel‐Wahab |
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| Institution: | 1. Department of Chemical Engineering, Texas A&M University at Qatar, Education City, Doha, Qatar;2. Department of Chemistry, Faculty of Sciences of Gabes, University of Gabes, Gabes, Tunisia;3. Department of Civil and Environmental Engineering, University of Houston, Houston, TX, USA |
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| Abstract: | In this work, the treatment of photographic processing wastewaters (PPW) by electro‐Fenton process has been investigated. The Influence of operating conditions on kinetics and efficiency of electro‐Fenton process has been evaluated using carbon felt cathode and platinium (Pt) or boron‐doped diamond (BDD) anode. The results of electro‐Fenton treatment of PPW have shown that nearly complete removal of total phenols was obtained for all combinations with pseudo‐first rate constants of 0.07, 0.012, and 0.018/min for carbon felt/Pt, carbon felt/BDD and Pt/BDD cathode/anode combinations, respectively. The combination of carbon felt cathode with BDD anode achieved the highest total organic carbon (TOC) removal of 90%, while it did not exeed 40% for carbon felt/Pt combination. Increasing current intensity and Fe2+ dose enhances the efficiency of electro‐Fenton process. However, increasing pH decreases TOC removal during the treatment of PPW by electro‐Fenton process. The highest efficiency of electro‐Fenton process using BDD anode can be explained by the contribution of direct and indirect oxidation routes in the degradation mechanism of organics including (i) oxidation via hydroxyl radicals generated from the catalytic decomposition of H2O2 and from water discharge on BDD anode, (ii) direct oxidation of certain organic compounds on BDD anode, and (iii) mediated oxidation with inorganic oxidants electrogenerated from anodic oxidation of supporting salts. |
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| Keywords: | Advanced oxidation processes Hydrogen peroxide TOC removal |
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