{"title":"Effective sonophotocatalytic degradation of tetracycline in water: Optimization, kinetic modeling, and degradation pathways","authors":"","doi":"10.1016/j.cep.2024.109979","DOIUrl":null,"url":null,"abstract":"<div><p>Hybrid advanced oxidation processes (AOPs) are gaining interest in degradation of variety of recalcitrant compounds for water and wastewater treatment, due to possible synergistic effects. The present study systematically evaluated the degradation of tetracycline (TC) with a sonophotocatalytic process combining acoustic cavitation (sonocavitation) and photocatalysis based on N-doped TiO<sub>2</sub> catalyst. The TC degradation rate constant was 2.4 × 10<sup>−2</sup> min<sup>−1</sup>, i.e., much higher than individual sonocatalytic (0.5 × 10<sup>−2</sup> min<sup>−1</sup>) and photocatalysis (0.6 × 10<sup>−2</sup> min<sup>−1</sup>) processes at the optimized conditions. The synergy index was 2.14, which reveals a significant improvement in the process performance. Maximum TC degradations of 55.5 ± 1.8 % for photocatalysis, 66.4 ± 1.8 % for sonocatalysis, and 79.5 ± 0.3 % for sonophotocatalysis were observed for 10 mg L<sup>−1</sup> initial TC concentration after 90 min of treatment. The photocatalytic experiments were extended further to 210 min to achieve a maximum degradation of 78.9 ± 0.2 % at the optimized condition<strong>.</strong> Scavenging experiments confirmed that hydroxyl radicals (<sup>•</sup>OH), electron holes (<em>h</em><sup>+</sup>), and superoxide radical anions (O<sub>2</sub><sup>−•</sup>) played a significant role in the degradation of TC. Further, the degradation intermediates for each process were identified and degradation pathways were proposed. Empirical kinetic models based on operational parameters were also developed and validated.</p></div>","PeriodicalId":9929,"journal":{"name":"Chemical Engineering and Processing - Process Intensification","volume":null,"pages":null},"PeriodicalIF":3.8000,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0255270124003179/pdfft?md5=3add864c268c7c6bd0d36169f7aa3439&pid=1-s2.0-S0255270124003179-main.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Chemical Engineering and Processing - Process Intensification","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0255270124003179","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ENERGY & FUELS","Score":null,"Total":0}
引用次数: 0
Abstract
Hybrid advanced oxidation processes (AOPs) are gaining interest in degradation of variety of recalcitrant compounds for water and wastewater treatment, due to possible synergistic effects. The present study systematically evaluated the degradation of tetracycline (TC) with a sonophotocatalytic process combining acoustic cavitation (sonocavitation) and photocatalysis based on N-doped TiO2 catalyst. The TC degradation rate constant was 2.4 × 10−2 min−1, i.e., much higher than individual sonocatalytic (0.5 × 10−2 min−1) and photocatalysis (0.6 × 10−2 min−1) processes at the optimized conditions. The synergy index was 2.14, which reveals a significant improvement in the process performance. Maximum TC degradations of 55.5 ± 1.8 % for photocatalysis, 66.4 ± 1.8 % for sonocatalysis, and 79.5 ± 0.3 % for sonophotocatalysis were observed for 10 mg L−1 initial TC concentration after 90 min of treatment. The photocatalytic experiments were extended further to 210 min to achieve a maximum degradation of 78.9 ± 0.2 % at the optimized condition. Scavenging experiments confirmed that hydroxyl radicals (•OH), electron holes (h+), and superoxide radical anions (O2−•) played a significant role in the degradation of TC. Further, the degradation intermediates for each process were identified and degradation pathways were proposed. Empirical kinetic models based on operational parameters were also developed and validated.
期刊介绍:
Chemical Engineering and Processing: Process Intensification is intended for practicing researchers in industry and academia, working in the field of Process Engineering and related to the subject of Process Intensification.Articles published in the Journal demonstrate how novel discoveries, developments and theories in the field of Process Engineering and in particular Process Intensification may be used for analysis and design of innovative equipment and processing methods with substantially improved sustainability, efficiency and environmental performance.