Investigating the potential of sepiolite-based adsorbents for levofloxacin removal from aqueous medium: experimental and optimization studies

Investigating the potential of sepiolite-based adsorbents for levofloxacin removal from aqueous medium: experimental and optimization studies | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Investigating the potential of sepiolite-based adsorbents for levofloxacin removal from aqueous medium: experimental and optimization studies Parisa Moradian, Behnaz Dahrazma, Ali Ebrahimi, Majid Bagheri, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6907573/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 19 Aug, 2025 Read the published version in Nanotechnology for Environmental Engineering → Version 1 posted 11 You are reading this latest preprint version Abstract This study evaluated the effectiveness of sepiolite nano-adsorbents (Sep) and Sep impregnated with manganese-oxide nanoparticles (Sep-MnO2) as cost-effective adsorbents for removing levofloxacin (LEV). Various analyses, including XRD, FTIR, and FESEM with EDS, were used to characterize the adsorbents. The Taguchi L25 experimental design was employed to optimize the adsorption process parameters (pH, contact time, adsorbent dose, initial concentration, and temperature) with the aim of maximizing LEV removal efficiency. Under optimal operating conditions, the maximum removal efficiencies for Sep and Sep-MnO₂ were 85.8% and 98.2%, respectively. The initial pH was identified as the most sensitive parameter, exhibiting peak performance at a pH of 3. The adsorption equilibrium data fit the Redlich–Peterson isotherm model more accurately. The maximum adsorption capacity was 11.46 and 30.98 mg/g for Sep and Sep-MnO2 adsorbents, respectively. The pseudo-second-order kinetic model provided the most accurate representation of the kinetic data. Thermodynamic analysis indicated that LEV adsorption on Sep is exothermic, whereas adsorption on Sep-MnO2 is endothermic and spontaneous. The adsorption mechanism was further explored through pH studies. The results showed that LEV adsorption involves cation exchange in acidic conditions, charge neutralization in neutral conditions, and proton transfer in alkaline conditions. Sepiolite Manganese-oxide nanoparticles Levofloxacin Adsorption Taguchi method Mechanism Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Full Text Additional Declarations No competing interests reported. Supplementary Files Highlights.docx Graphicalabstract.jpg Cite Share Download PDF Status: Published Journal Publication published 19 Aug, 2025 Read the published version in Nanotechnology for Environmental Engineering → Version 1 posted Editorial decision: Revision requested 17 Jul, 2025 Reviews received at journal 01 Jul, 2025 Reviews received at journal 30 Jun, 2025 Reviewers agreed at journal 28 Jun, 2025 Reviewers agreed at journal 26 Jun, 2025 Reviews received at journal 26 Jun, 2025 Reviewers agreed at journal 24 Jun, 2025 Reviewers invited by journal 23 Jun, 2025 Editor assigned by journal 18 Jun, 2025 Submission checks completed at journal 17 Jun, 2025 First submitted to journal 16 Jun, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6907573","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":475503578,"identity":"f13f4819-025b-45c4-a44a-92ae56810dfa","order_by":0,"name":"Parisa 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3","display":"","copyAsset":false,"role":"figure","size":884569,"visible":true,"origin":"","legend":"\u003cp\u003eSEM and EDS analyses of Sep (a, b, and c) before LEV adsorption and (d, e, and f) after LEV adsorption.\u003c/p\u003e","description":"","filename":"Figure3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6907573/v1/e1f4c4eb95addbefaf4eefca.jpg"},{"id":85385161,"identity":"d5837a80-cefb-4972-82c6-a98cb17b6494","added_by":"auto","created_at":"2025-06-25 09:41:55","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":853012,"visible":true,"origin":"","legend":"\u003cp\u003eSEM and EDS analyses of Sep-MnO\u003csub\u003e2\u003c/sub\u003e (a, b, and c) before LEV adsorption and (d, e, and f) after LEV adsorption.\u003c/p\u003e","description":"","filename":"Figure4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6907573/v1/0d733aabed9410d2b700a5c0.jpg"},{"id":85385160,"identity":"3d6ffb84-d3ed-40af-94cd-598fa4e28fab","added_by":"auto","created_at":"2025-06-25 09:41:55","extension":"jpg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":117568,"visible":true,"origin":"","legend":"\u003cp\u003eResponse distribution of \u0026nbsp;ratios for LEV removal by (a) Sep, and (b) Sep-MnO\u003csub\u003e2\u003c/sub\u003e adsorbents.\u003c/p\u003e","description":"","filename":"Figure5.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6907573/v1/484022b2f909c01fc3258c47.jpg"},{"id":85383067,"identity":"1adaffa2-ba94-4b81-837e-748533157685","added_by":"auto","created_at":"2025-06-25 09:33:55","extension":"jpg","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":1027493,"visible":true,"origin":"","legend":"\u003cp\u003eNon-linear isotherm plots for LEV adsorption onto (a) Sep, and (b) Sep-MnO\u003csub\u003e2\u003c/sub\u003e.\u003c/p\u003e","description":"","filename":"Figure6.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6907573/v1/04258f64a66d1d8a0b08f5dd.jpg"},{"id":85385675,"identity":"608969de-fcaf-4c4e-a272-6041db8cd42d","added_by":"auto","created_at":"2025-06-25 09:49:55","extension":"jpg","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":57132,"visible":true,"origin":"","legend":"\u003cp\u003e(a) Pseudo-first-order, (b) Pseudo-second-order and, (c) Elovich plots for LEV uptake by Sep and Sep-MnO\u003csub\u003e2\u003c/sub\u003e.\u003c/p\u003e","description":"","filename":"Figure7.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6907573/v1/ff0d73fd9a0c7a8a75e147fa.jpg"},{"id":85385164,"identity":"483c4aaf-15d7-49b1-a7cb-218202f52bd0","added_by":"auto","created_at":"2025-06-25 09:41:55","extension":"jpg","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":41665,"visible":true,"origin":"","legend":"\u003cp\u003e(a) Intraparticle diffusion and, (b) Bangham’s plots for adsorption of LEV by Sep and Sep-MnO\u003csub\u003e2\u003c/sub\u003e.\u003c/p\u003e","description":"","filename":"Figure8.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6907573/v1/bb417a1dd854fc63cf7feb09.jpg"},{"id":89847277,"identity":"683fb93c-794d-4fcf-b0df-5a76fe652679","added_by":"auto","created_at":"2025-08-25 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