Aqueous phase degradation of methyl paraben using UV-activated persulfate method
| Autor: | Ki Jung Paeng, Moonis Ali Khan, Mayur B. Kurade, Rajesh Kumar, Sun Joon Kim, Sarita Dhaka, Byong-Hun Jeon |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
chemistry.chemical_classification
Ethanol Aqueous solution General Chemical Engineering Radical Inorganic chemistry Kinetics Aqueous two-phase system 02 engineering and technology General Chemistry 010501 environmental sciences 021001 nanoscience & nanotechnology Persulfate 01 natural sciences Industrial and Manufacturing Engineering chemistry.chemical_compound chemistry Environmental Chemistry Humic acid Degradation (geology) 0210 nano-technology 0105 earth and related environmental sciences |
| Zdroj: | Chemical Engineering Journal. 321:11-19 |
| ISSN: | 1385-8947 |
| Popis: | Methyl paraben (MP), a widely used preservative, exhibits endocrine-disrupting properties with estrogenic activities. The aqueous phase degradation of MP, using UV-activated persulfate method, was investigated in the present study. The combination of UV irradiation and persulfate anion successfully degraded MP showing 98.9% removal within 90 min. A quenching experiment using ethanol (EtOH) and tert -butyl alcohol (TBA) showed the presence of both radicals (OH and SO 4 – ) in the system; near neutral pH SO 4 – radical was the major species. The influence of various factors such as persulfate dose, initial MP concentration, solution pH, and water matrix components on the degradation kinetics was examined in view of the practical applications of the developed process. The degradation rate of MP was considerably increased as the amount of persulfate increased. The degradation of MP in the UV/persulfate system was pH dependent and more promising near neutral pH (6.5) conditions. The presence of anions such as Cl − , HPO 4 2− and HCO 3 − showed inhibitory effect towards MP degradation. The presence of humic acid also suppressed the degradation efficiency of MP. The reaction rate followed pseudo-first-order kinetics for all of the degradations. The degradation of MP by UV/persulfate treatment led to the production of seven transformation byproducts, which were identified using ultra-high-performance liquid chromatography-mass spectrometry (UPLC-MS). A degradation pathway for MP degradation was also proposed. The results of the present study reveal that the UV/persulfate process could be an effective approach to remove MP from aqueous solutions. |
| Databáze: | OpenAIRE |
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