Solar Heterogenous Photocatalytic Degradation of Methylthionine Chloride on a Flat Plate Reactor: Effect of pH and H<sub>2</sub>O<sub>2</sub> Addition
Methylthionine chloride (MTC) is a compound with several applications both in the clinical and medical industries. Nevertheless, such compounds can become an environmental problem, as they are not properly treated by wastewater treatment plants. This objective of this work was to study MTC degradati...
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MDPI AG
2022-01-01
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| Online Access: | https://www.mdpi.com/2073-4344/12/2/132 |
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| author | Pablo E. Zaruma-Arias Cynthia M. Núñez-Núñez Luis A. González-Burciaga José B. Proal-Nájera |
| author_facet | Pablo E. Zaruma-Arias Cynthia M. Núñez-Núñez Luis A. González-Burciaga José B. Proal-Nájera |
| author_sort | Pablo E. Zaruma-Arias |
| collection | DOAJ |
| description | Methylthionine chloride (MTC) is a compound with several applications both in the clinical and medical industries. Nevertheless, such compounds can become an environmental problem, as they are not properly treated by wastewater treatment plants. This objective of this work was to study MTC degradation in a flat plate reactor through solar photolysis and heterogeneous photocatalysis processes with TiO<sub>2</sub> as a catalyst. In addition to the processes, three pH (3.5, 6.5, and 9) and the effect of H<sub>2</sub>O<sub>2</sub> addition (no dose, 0.5, and 1 mM/L) were tested. The results show that acidic pH is the most appropriate for MTC degradation, which ranged between 56% and 68.7% for photolysis and between 76% and 86.7% in photocatalysis. The H<sub>2</sub>O<sub>2</sub> addition resulted in lower degradation in all cases, leading the authors to conclude that the presence of peroxide actually hinders degradation in solar photolysis and photocatalysis processes. Statistical analysis showed that the constant rate reactions calculated for every process, under the same conditions of pH and H<sub>2</sub>O<sub>2</sub> addition, are significantly different from one another, and the three factors considered for experimental design (process, pH, and H<sub>2</sub>O<sub>2</sub>) have a statistically significant effect on MTC degradation. The collector area per order confirmed higher efficiency for photocatalysis when compared to photolysis processes. |
| first_indexed | 2024-03-09T22:22:09Z |
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| spelling | doaj.art-69b2e35112b74141904b793c9c8098002023-11-23T19:11:47ZengMDPI AGCatalysts2073-43442022-01-0112213210.3390/catal12020132Solar Heterogenous Photocatalytic Degradation of Methylthionine Chloride on a Flat Plate Reactor: Effect of pH and H<sub>2</sub>O<sub>2</sub> AdditionPablo E. Zaruma-Arias0Cynthia M. Núñez-Núñez1Luis A. González-Burciaga2José B. Proal-Nájera3Instituto Politécnico Nacional, CIIDIR-Unidad Durango, Calle Sigma 119, Fracc. 20 de Noviembre II, Durango 34220, MexicoIngeniería en Tecnología Ambiental, Universidad Politécnica de Durango, Carretera Durango-México km 9.5, Col. Dolores Hidalgo, Durango 34300, MexicoInstituto Politécnico Nacional, CIIDIR-Unidad Durango, Calle Sigma 119, Fracc. 20 de Noviembre II, Durango 34220, MexicoInstituto Politécnico Nacional, CIIDIR-Unidad Durango, Calle Sigma 119, Fracc. 20 de Noviembre II, Durango 34220, MexicoMethylthionine chloride (MTC) is a compound with several applications both in the clinical and medical industries. Nevertheless, such compounds can become an environmental problem, as they are not properly treated by wastewater treatment plants. This objective of this work was to study MTC degradation in a flat plate reactor through solar photolysis and heterogeneous photocatalysis processes with TiO<sub>2</sub> as a catalyst. In addition to the processes, three pH (3.5, 6.5, and 9) and the effect of H<sub>2</sub>O<sub>2</sub> addition (no dose, 0.5, and 1 mM/L) were tested. The results show that acidic pH is the most appropriate for MTC degradation, which ranged between 56% and 68.7% for photolysis and between 76% and 86.7% in photocatalysis. The H<sub>2</sub>O<sub>2</sub> addition resulted in lower degradation in all cases, leading the authors to conclude that the presence of peroxide actually hinders degradation in solar photolysis and photocatalysis processes. Statistical analysis showed that the constant rate reactions calculated for every process, under the same conditions of pH and H<sub>2</sub>O<sub>2</sub> addition, are significantly different from one another, and the three factors considered for experimental design (process, pH, and H<sub>2</sub>O<sub>2</sub>) have a statistically significant effect on MTC degradation. The collector area per order confirmed higher efficiency for photocatalysis when compared to photolysis processes.https://www.mdpi.com/2073-4344/12/2/132advanced oxidation processesbatch modesolar radiationsolar-driven systemstitanium dioxide |
| spellingShingle | Pablo E. Zaruma-Arias Cynthia M. Núñez-Núñez Luis A. González-Burciaga José B. Proal-Nájera Solar Heterogenous Photocatalytic Degradation of Methylthionine Chloride on a Flat Plate Reactor: Effect of pH and H<sub>2</sub>O<sub>2</sub> Addition Catalysts advanced oxidation processes batch mode solar radiation solar-driven systems titanium dioxide |
| title | Solar Heterogenous Photocatalytic Degradation of Methylthionine Chloride on a Flat Plate Reactor: Effect of pH and H<sub>2</sub>O<sub>2</sub> Addition |
| title_full | Solar Heterogenous Photocatalytic Degradation of Methylthionine Chloride on a Flat Plate Reactor: Effect of pH and H<sub>2</sub>O<sub>2</sub> Addition |
| title_fullStr | Solar Heterogenous Photocatalytic Degradation of Methylthionine Chloride on a Flat Plate Reactor: Effect of pH and H<sub>2</sub>O<sub>2</sub> Addition |
| title_full_unstemmed | Solar Heterogenous Photocatalytic Degradation of Methylthionine Chloride on a Flat Plate Reactor: Effect of pH and H<sub>2</sub>O<sub>2</sub> Addition |
| title_short | Solar Heterogenous Photocatalytic Degradation of Methylthionine Chloride on a Flat Plate Reactor: Effect of pH and H<sub>2</sub>O<sub>2</sub> Addition |
| title_sort | solar heterogenous photocatalytic degradation of methylthionine chloride on a flat plate reactor effect of ph and h sub 2 sub o sub 2 sub addition |
| topic | advanced oxidation processes batch mode solar radiation solar-driven systems titanium dioxide |
| url | https://www.mdpi.com/2073-4344/12/2/132 |
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