Performance and Mechanism of Sulfathiazole Adsorption by Magnetic Biochar: Promoting Effect of Co-existing Polystyrene and Simultaneous Removal

Performance and Mechanism of Sulfathiazole Adsorption by Magnetic Biochar: Promoting Effect of Co-existing Polystyrene and Simultaneous Removal | 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 Performance and Mechanism of Sulfathiazole Adsorption by Magnetic Biochar: Promoting Effect of Co-existing Polystyrene and Simultaneous Removal Xilong Zhang, Zihan Tang, Fei Liu, Xiuping Hong, Yingying Zhang, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7974902/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 14 Jan, 2026 Read the published version in Water, Air, & Soil Pollution → Version 1 posted You are reading this latest preprint version Abstract Antibiotics and microplastics (MPs) combined pollution threatens aquatic ecosystems and human health. Polystyrene (PS, a typical MP), widely detected in water, interacts with sulfathiazole (STZ, a sulfonamide antibiotic), affecting wastewater treatment. In this study, a novel magnetic biochar (MBC) was synthesized via co-precipitation, and its performance in removing STZ under the co-existence of PS was systematically evaluated using experiments and theoretical calculations. The MBC exhibited excellent superparamagnetism (saturation magnetization: 11 emu·g⁻¹) and a high specific surface area (702.67 m²/g), enabling efficient separation and recovery, enabling efficient separation and recovery. In single-pollutant systems (only STZ), the MBC showed an adsorption capacity of 39.31 mg・g⁻¹ for STZ; notably, in co-existing systems (PS + STZ), the presence of PS exerted a promoting effect, boosting the STZ adsorption capacity to 42.49 mg・g⁻¹ (removal rate > 98%), with optimal performance under neutral conditions (pH 5–7). Notably, while removing STZ, MBC still maintains high efficiency in PS removal, with PS removal rate reaching up to 98%. From a kinetic perspective, in the single STZ system, STZ adsorption relies on hydrogen bonding and π–π conjugation. However, in the system with co-existing PS and STZ, PS forms PS-STZ complexes. These complexes anchor to the hydrophobic regions of MBC, and at the same time, the polar groups of STZ bind to the polar sites of MBC. This further enhances the stability of the binding between PS and MBC. This study provides a feasible strategy for the synergistic removal of antibiotics and microplastics. Magnetic biochar Polystyrene Sulfathiazole Adsorption behavior Adsorption mechanism Full Text Additional Declarations No competing interests reported. Supplementary Files supplement.docx graphicalabstract.docx Cite Share Download PDF Status: Published Journal Publication published 14 Jan, 2026 Read the published version in Water, Air, & Soil Pollution → Version 1 posted 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-7974902","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":545937972,"identity":"4c1cd60a-c946-494a-ba5c-ca5e30c5324d","order_by":0,"name":"Xilong Zhang","email":"","orcid":"","institution":"Huaibei Normal University","correspondingAuthor":false,"prefix":"","firstName":"Xilong","middleName":"","lastName":"Zhang","suffix":""},{"id":545937973,"identity":"bd47bf5b-fa93-4153-8ee9-03dee82d74f5","order_by":1,"name":"Zihan Tang","email":"","orcid":"","institution":"Huaibei Normal 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Removal","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Magnetic biochar, Polystyrene, Sulfathiazole, Adsorption behavior, Adsorption mechanism","lastPublishedDoi":"10.21203/rs.3.rs-7974902/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7974902/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eAntibiotics and microplastics (MPs) combined pollution threatens aquatic ecosystems and human health. Polystyrene (PS, a typical MP), widely detected in water, interacts with sulfathiazole (STZ, a sulfonamide antibiotic), affecting wastewater treatment. In this study, a novel magnetic biochar (MBC) was synthesized via co-precipitation, and its performance in removing STZ under the co-existence of PS was systematically evaluated using experiments and theoretical calculations. The MBC exhibited excellent superparamagnetism (saturation magnetization: 11 emu\u0026middot;g⁻\u0026sup1;) and a high specific surface area (702.67 m\u0026sup2;/g), enabling efficient separation and recovery, enabling efficient separation and recovery. In single-pollutant systems (only STZ), the MBC showed an adsorption capacity of 39.31 mg・g⁻\u0026sup1; for STZ; notably, in co-existing systems (PS\u0026thinsp;+\u0026thinsp;STZ), the presence of PS exerted a promoting effect, boosting the STZ adsorption capacity to 42.49 mg・g⁻\u0026sup1; (removal rate\u0026thinsp;\u0026gt;\u0026thinsp;98%), with optimal performance under neutral conditions (pH 5\u0026ndash;7). Notably, while removing STZ, MBC still maintains high efficiency in PS removal, with PS removal rate reaching up to 98%. From a kinetic perspective, in the single STZ system, STZ adsorption relies on hydrogen bonding and π\u0026ndash;π conjugation. However, in the system with co-existing PS and STZ, PS forms PS-STZ complexes. These complexes anchor to the hydrophobic regions of MBC, and at the same time, the polar groups of STZ bind to the polar sites of MBC. This further enhances the stability of the binding between PS and MBC. This study provides a feasible strategy for the synergistic removal of antibiotics and microplastics.\u003c/p\u003e","manuscriptTitle":"Performance and Mechanism of Sulfathiazole Adsorption by Magnetic Biochar: Promoting Effect of Co-existing Polystyrene and Simultaneous Removal","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-18 05:47:38","doi":"10.21203/rs.3.rs-7974902/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"9eb8da30-372e-4cc1-b779-d86f738cbee0","owner":[],"postedDate":"November 18th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-01-19T16:50:04+00:00","versionOfRecord":{"articleIdentity":"rs-7974902","link":"https://doi.org/10.1007/s11270-026-09104-0","journal":{"identity":"water-air-and-soil-pollution","isVorOnly":false,"title":"Water, Air, \u0026 Soil Pollution"},"publishedOn":"2026-01-14 16:30:56","publishedOnDateReadable":"January 14th, 2026"},"versionCreatedAt":"2025-11-18 05:47:38","video":"","vorDoi":"10.1007/s11270-026-09104-0","vorDoiUrl":"https://doi.org/10.1007/s11270-026-09104-0","workflowStages":[]},"version":"v1","identity":"rs-7974902","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7974902","identity":"rs-7974902","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}