Enhanced and Efficient Removal of U(VI) from Aqueous Solution by a Hydroxyapatite-Bamboo Biochar Composite: Performance and Mechanism

Enhanced and Efficient Removal of U(VI) from Aqueous Solution by a Hydroxyapatite-Bamboo Biochar Composite: Performance and Mechanism | 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 Enhanced and Efficient Removal of U(VI) from Aqueous Solution by a Hydroxyapatite-Bamboo Biochar Composite: Performance and Mechanism Cheng Chen, Pengcheng Xian, Yanjing Yang, Liang Huang, Fengyao Fan, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9411837/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract In this study, a hydroxyapatite-bamboo biochar (HAP-BBC) composite material was successfully synthesized via pyrolysis and water-bath co-precipitation methods. Its adsorption performance for U(VI) in aqueous solution was systematically investigated. Experimental results indicated that under pH 4.0–5.0, the removal efficiency for 50 mg/L U(VI) solution exceeded 98%. The adsorption process was well described by the Langmuir isotherm and the pseudo-second-order kinetic model, indicating a predominantly monolayer chemisorption process, with a theoretical maximum adsorption capacity of 649.35 mg/g. Coexisting ion experiments showed that the material exhibited excellent resistance to interference from K + , SO 4 2‒ , Mg 2+ , and Zn 2+ , while Ca 2+ , F ‒ , PO 4 3‒, and Al 3+ exhibited varying degrees of inhibitory effects. A combination of characterization techniques, including FTIR, XRD, XPS, BET, and SEM-EDS, revealed that the immobilization of U(VI) was governed by synergistic mechanisms, chiefly via dissolution-precipitation (forming autunite), surface complexation (with ‒OH and PO 4 3‒ groups), and ion exchange (between UO 2 2+ and Ca 2+ in the HAP lattice). The composite material integrates high adsorption capacity, strong selectivity, and good cyclic stability, presenting promising application prospects for the treatment of uranium-containing wastewater. U(Ⅵ) adsorption Hydroxyapatite Bamboo-based biochar Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted 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. 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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-9411837","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":626809240,"identity":"08b1f348-f032-45b6-bab2-b525d2c8ac0f","order_by":0,"name":"Cheng Chen","email":"","orcid":"","institution":"Chengdu University of Technology","correspondingAuthor":false,"prefix":"","firstName":"Cheng","middleName":"","lastName":"Chen","suffix":""},{"id":626809243,"identity":"f59d48cc-7e84-49bb-9006-4d268e457847","order_by":1,"name":"Pengcheng Xian","email":"","orcid":"","institution":"Chengdu University of Technology","correspondingAuthor":false,"prefix":"","firstName":"Pengcheng","middleName":"","lastName":"Xian","suffix":""},{"id":626809246,"identity":"7a167840-ae2a-4ba8-b523-4c930d3cb5f4","order_by":2,"name":"Yanjing Yang","email":"","orcid":"","institution":"Chengdu University of Technology","correspondingAuthor":false,"prefix":"","firstName":"Yanjing","middleName":"","lastName":"Yang","suffix":""},{"id":626809249,"identity":"10208073-c83c-47ad-af1c-998428fff511","order_by":3,"name":"Liang Huang","email":"","orcid":"","institution":"Chengdu University of Technology","correspondingAuthor":false,"prefix":"","firstName":"Liang","middleName":"","lastName":"Huang","suffix":""},{"id":626809250,"identity":"0faae865-a8b4-4b44-8068-48340dd6a628","order_by":4,"name":"Fengyao Fan","email":"","orcid":"","institution":"Chengdu University of Technology","correspondingAuthor":false,"prefix":"","firstName":"Fengyao","middleName":"","lastName":"Fan","suffix":""},{"id":626809251,"identity":"5e841b65-ea99-4855-8699-c97806976912","order_by":5,"name":"Chunhai Lu","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAn0lEQVRIiWNgGAWjYBACPgYGNmYGAxsefvYGIrWwQbSkyUj2HCBJC8NhG4MbDsRqkUh+9rig4DwPww0Gxg8fc4jSkmZuPMPgNg/j7AZmyZnbiNKSwybNA9TCLHOAjZmXBC3neNgkEkjTcoCHh3gtPM/MgFqSeSR4DjYT5xd+9uRn0jx/7Oztjzcf/PCRGC1IgLGBNPWjYBSMglEwCnADAPZSKJ2mlbfwAAAAAElFTkSuQmCC","orcid":"","institution":"Chengdu University of Technology","correspondingAuthor":true,"prefix":"","firstName":"Chunhai","middleName":"","lastName":"Lu","suffix":""}],"badges":[],"createdAt":"2026-04-14 07:24:06","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9411837/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9411837/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":108092099,"identity":"f2e5dfbc-5e99-4046-9019-29ace3bdf72b","added_by":"auto","created_at":"2026-04-29 09:27:51","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":566063,"visible":true,"origin":"","legend":"","description":"","filename":"Manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9411837/v1_covered_89665aa2-71a8-46de-ae7c-c53beb45d525.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Enhanced and Efficient Removal of U(VI) from Aqueous Solution by a Hydroxyapatite-Bamboo Biochar Composite: Performance and Mechanism","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"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":"U(Ⅵ) adsorption, Hydroxyapatite, Bamboo-based biochar","lastPublishedDoi":"10.21203/rs.3.rs-9411837/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9411837/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eIn this study, a hydroxyapatite-bamboo biochar (HAP-BBC) composite material was successfully synthesized via pyrolysis and water-bath co-precipitation methods. Its adsorption performance for U(VI) in aqueous solution was systematically investigated. Experimental results indicated that under pH 4.0\u0026ndash;5.0, the removal efficiency for 50 mg/L U(VI) solution exceeded 98%. The adsorption process was well described by the Langmuir isotherm and the pseudo-second-order kinetic model, indicating a predominantly monolayer chemisorption process, with a theoretical maximum adsorption capacity of 649.35 mg/g. Coexisting ion experiments showed that the material exhibited excellent resistance to interference from K\u003csup\u003e+\u003c/sup\u003e, SO\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e2‒\u003c/sup\u003e, Mg\u003csup\u003e2+\u003c/sup\u003e, and Zn\u003csup\u003e2+\u003c/sup\u003e, while Ca\u003csup\u003e2+\u003c/sup\u003e, F\u003csup\u003e‒\u003c/sup\u003e, PO\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e3‒,\u003c/sup\u003e and Al\u003csup\u003e3+\u003c/sup\u003e exhibited varying degrees of inhibitory effects. A combination of characterization techniques, including FTIR, XRD, XPS, BET, and SEM-EDS, revealed that the immobilization of U(VI) was governed by synergistic mechanisms, chiefly via dissolution-precipitation (forming autunite), surface complexation (with ‒OH and PO\u003csub\u003e4\u003c/sub\u003e\u003csup\u003e3‒\u003c/sup\u003e groups), and ion exchange (between UO\u003csub\u003e2\u003c/sub\u003e\u003csup\u003e2+\u003c/sup\u003e and Ca\u003csup\u003e2+\u003c/sup\u003e in the HAP lattice). The composite material integrates high adsorption capacity, strong selectivity, and good cyclic stability, presenting promising application prospects for the treatment of uranium-containing wastewater.\u003c/p\u003e","manuscriptTitle":"Enhanced and Efficient Removal of U(VI) from Aqueous Solution by a Hydroxyapatite-Bamboo Biochar Composite: Performance and Mechanism","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-04-29 09:27:43","doi":"10.21203/rs.3.rs-9411837/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":"408373b3-6d7d-4916-ae9f-f6dc2aaac28c","owner":[],"postedDate":"April 29th, 2026","published":true,"recentEditorialEvents":[{"type":"reviewerAgreed","content":"325559676482748480523129511109203781191","date":"2026-05-06T07:46:48+00:00","index":14,"fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-04-29T09:27:43+00:00","versionOfRecord":[],"versionCreatedAt":"2026-04-29 09:27:43","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9411837","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9411837","identity":"rs-9411837","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}