Photodegradation of Methylene Blue Using a UV/H<sub>2</sub>O<sub>2</sub> Irradiation System
This study presents an efficient way to degrade methylene blue (MB) present in water via photodegradation using H<sub>2</sub>O<sub>2</sub> as an oxidant in the presence of UV irradiation and without the use of a catalyst. The reaction variables, employed to evaluate the perfo...
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| Format: | Article |
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MDPI AG
2024-01-01
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| Series: | Water |
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| Online Access: | https://www.mdpi.com/2073-4441/16/3/453 |
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| author | Mohammad Ashraf Ali Ibrahim M. Maafa Isam Y. Qudsieh |
| author_facet | Mohammad Ashraf Ali Ibrahim M. Maafa Isam Y. Qudsieh |
| author_sort | Mohammad Ashraf Ali |
| collection | DOAJ |
| description | This study presents an efficient way to degrade methylene blue (MB) present in water via photodegradation using H<sub>2</sub>O<sub>2</sub> as an oxidant in the presence of UV irradiation and without the use of a catalyst. The reaction variables, employed to evaluate the performance of the photodegradation process using the UV/H<sub>2</sub>O<sub>2</sub> system, were the amount of H<sub>2</sub>O<sub>2</sub> in the reacting solution and the initial concentration of methylene blue. The degradation of methylene blue in the presence of H<sub>2</sub>O<sub>2</sub> was not observed during agitation in darkness. The degradation time decreased as the H<sub>2</sub>O<sub>2</sub> concentration increased after the ideal concentration was reached. At this stage, as it began to scavenge the generated hydroxyl radicals, the rate of degradation became inversely proportional to the concentration of H<sub>2</sub>O<sub>2</sub>. An increase in the quantities of MB and H<sub>2</sub>O<sub>2</sub> improved the degradation efficiency because the oxidation process was aided by using the appropriate amount of H<sub>2</sub>O<sub>2</sub> and an ideal length of UV light exposure. The experimental data obtained were well-fitted to zero-order reaction kinetics based on the high values of the correlation coefficient. It is believed that the OH radicals (OH<sup>●</sup>) generated during the breakdown of H<sub>2</sub>O<sub>2</sub> and the generated O<sub>2</sub><sup>●−</sup> species attack the MB molecules and produce MB radicals (MB<sup>●</sup>). These MB radicals further experience oxidation and convert to intermediates and finally to CO<sub>2</sub> and H<sub>2</sub>O. The UV/H<sub>2</sub>O<sub>2</sub> system proved to be quite efficient for the photodegradation of methylene blue without the use of any solid catalyst. This UV/H<sub>2</sub>O<sub>2</sub> system can be employed in the degradation of other organic pollutants in industrial wastewater. |
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| institution | Directory Open Access Journal |
| issn | 2073-4441 |
| language | English |
| last_indexed | 2024-03-08T03:47:00Z |
| publishDate | 2024-01-01 |
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| spelling | doaj.art-9934bf35cbcb440cbff52677827f133a2024-02-09T15:24:44ZengMDPI AGWater2073-44412024-01-0116345310.3390/w16030453Photodegradation of Methylene Blue Using a UV/H<sub>2</sub>O<sub>2</sub> Irradiation SystemMohammad Ashraf Ali0Ibrahim M. Maafa1Isam Y. Qudsieh2Department of Chemical Engineering, College of Engineering, Jazan University, Jazan 45142, Saudi ArabiaDepartment of Chemical Engineering, College of Engineering, Jazan University, Jazan 45142, Saudi ArabiaDepartment of Chemical Engineering, College of Engineering, Jazan University, Jazan 45142, Saudi ArabiaThis study presents an efficient way to degrade methylene blue (MB) present in water via photodegradation using H<sub>2</sub>O<sub>2</sub> as an oxidant in the presence of UV irradiation and without the use of a catalyst. The reaction variables, employed to evaluate the performance of the photodegradation process using the UV/H<sub>2</sub>O<sub>2</sub> system, were the amount of H<sub>2</sub>O<sub>2</sub> in the reacting solution and the initial concentration of methylene blue. The degradation of methylene blue in the presence of H<sub>2</sub>O<sub>2</sub> was not observed during agitation in darkness. The degradation time decreased as the H<sub>2</sub>O<sub>2</sub> concentration increased after the ideal concentration was reached. At this stage, as it began to scavenge the generated hydroxyl radicals, the rate of degradation became inversely proportional to the concentration of H<sub>2</sub>O<sub>2</sub>. An increase in the quantities of MB and H<sub>2</sub>O<sub>2</sub> improved the degradation efficiency because the oxidation process was aided by using the appropriate amount of H<sub>2</sub>O<sub>2</sub> and an ideal length of UV light exposure. The experimental data obtained were well-fitted to zero-order reaction kinetics based on the high values of the correlation coefficient. It is believed that the OH radicals (OH<sup>●</sup>) generated during the breakdown of H<sub>2</sub>O<sub>2</sub> and the generated O<sub>2</sub><sup>●−</sup> species attack the MB molecules and produce MB radicals (MB<sup>●</sup>). These MB radicals further experience oxidation and convert to intermediates and finally to CO<sub>2</sub> and H<sub>2</sub>O. The UV/H<sub>2</sub>O<sub>2</sub> system proved to be quite efficient for the photodegradation of methylene blue without the use of any solid catalyst. This UV/H<sub>2</sub>O<sub>2</sub> system can be employed in the degradation of other organic pollutants in industrial wastewater.https://www.mdpi.com/2073-4441/16/3/453photodegradationmethylene blueUV/H<sub>2</sub>O<sub>2</sub> irradiation systemzero-order reaction kinetics |
| spellingShingle | Mohammad Ashraf Ali Ibrahim M. Maafa Isam Y. Qudsieh Photodegradation of Methylene Blue Using a UV/H<sub>2</sub>O<sub>2</sub> Irradiation System Water photodegradation methylene blue UV/H<sub>2</sub>O<sub>2</sub> irradiation system zero-order reaction kinetics |
| title | Photodegradation of Methylene Blue Using a UV/H<sub>2</sub>O<sub>2</sub> Irradiation System |
| title_full | Photodegradation of Methylene Blue Using a UV/H<sub>2</sub>O<sub>2</sub> Irradiation System |
| title_fullStr | Photodegradation of Methylene Blue Using a UV/H<sub>2</sub>O<sub>2</sub> Irradiation System |
| title_full_unstemmed | Photodegradation of Methylene Blue Using a UV/H<sub>2</sub>O<sub>2</sub> Irradiation System |
| title_short | Photodegradation of Methylene Blue Using a UV/H<sub>2</sub>O<sub>2</sub> Irradiation System |
| title_sort | photodegradation of methylene blue using a uv h sub 2 sub o sub 2 sub irradiation system |
| topic | photodegradation methylene blue UV/H<sub>2</sub>O<sub>2</sub> irradiation system zero-order reaction kinetics |
| url | https://www.mdpi.com/2073-4441/16/3/453 |
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