Degradation of naphthalene with magnetic bio-char activate hydrogen peroxide: Synergism of bio-char and Fe–Mn binary oxides
| Autor: | Min Cheng, Mingming Zhang, Jiangfan He, Cui Lai, Shiyu Liu, Minfang Li, Guangming Zeng, Lei Qin, Liang Chen, Danlian Huang, Huang Fanglong, Bisheng Li, Yujin Zhang, Ling Li |
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| Rok vydání: | 2019 |
| Předmět: |
Environmental Engineering
Iron Radical 0208 environmental biotechnology Inorganic chemistry 02 engineering and technology Naphthalenes 010501 environmental sciences 01 natural sciences Catalysis Industrial wastewater treatment chemistry.chemical_compound Adsorption Char Hydrogen peroxide Waste Management and Disposal 0105 earth and related environmental sciences Water Science and Technology Civil and Structural Engineering Naphthalene Ecological Modeling Oxides Hydrogen Peroxide Pollution 020801 environmental engineering chemistry Charcoal Hydroxyl radical Oxidation-Reduction |
| Zdroj: | Water Research. 160:238-248 |
| ISSN: | 0043-1354 |
| DOI: | 10.1016/j.watres.2019.05.081 |
| Popis: | This study investigated the hydrogen peroxide (H2O2) activation potential of Fe–Mn binary oxides modified bio-char (FeMn/bio-char) for the degradation of naphthalene, the dominant PAHs in drinking water. Results showed that FeMn/bio-char exhibited 80.7- and 2.18-times decomposition rates towards H2O2 than that of pure bio-char and Fe–Mn binary oxides, respectively, and consequently the FeMn/bio-char/H2O2 photo-Fenton system presented highest naphthalene removal efficiency. The enhanced catalytic activity could be ascribed to the synergistic effect of the combination of bio-char and Fe–Mn binary oxides, such as promoting the adsorption capacity towards contaminant, increasing concentration of persistent free radicals (PFRs) and introducing Fe–Mn binary oxides as new activator. According to the batch-scale experiments, FeMn/bio-char/H2O2 photo-Fenton system could degrade naphthalene effectively at a wide pH ranges, and 82.2% of naphthalene was degraded under natural pH of 5.6 within 148 min. Free radicals quenching studies and electron spin resonance (ESR) analyses verified that the dominant free radical within FeMn/bio-char/H2O2 photo-Fenton system was hydroxyl radical (•OH). According to the preliminary analysis, the generation of •OH were ascribed to the activation of H2O2 by Fe (II), Mn (II) and PFRs on the catalyst surface. The mainly degradation intermediates of naphthalene were identified by GC-MS analysis. Consequently, the possible degradation pathways were proposed. Moreover, naphthalene degradation experiments were also conducted in river, tap water, industrial wastewater as well as medical wastewater, and the results indicated that the FeMn/bio-char/H2O2 photo-Fenton system was effective in the treatment of naphthalene in natural waters. This study brings a valuable insight for the potential environmental applications of modified bio-char. |
| Databáze: | OpenAIRE |
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