The assessment of biochar-metal composite in removal of direct blue-71 from aqueous solution

The assessment of biochar-metal composite in removal of direct blue-71 from aqueous solution | 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 The assessment of biochar-metal composite in removal of direct blue-71 from aqueous solution Hanyeh Sepahvand, Fardin Sadeghzadeh, Bahi Jalili, Maedeh Parichehre This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8457392/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, biochar, metal-coated biochar, and biochar-metal composites of different metals were prepared using rice straw as the raw material. Three elements, iron, copper, and zinc, were selected for preparing the adsorbents for further tests. In this study, we used Direct Blue 71(DB71) as an anionic pollutant sample, which is abundant in the study region. The effects of pH (3.0–9.0), adsorption time (0-420 min), and sorbent dosage (2.5 25 g L -1 ) on the removal of DB71 were investigated, and a regeneration experiment was performed. In order to compare the effect of temperature, a leaching experiment was performed using biochar and metal-biochar composites produced at two temperatures (300 and 600°C) as adsorbents to remove DB71 from water. The results showed that the maximum adsorption capacity of DB71 was obtained at 180 min, pH 6, and dosage of 12.5 g L -1 . The Fe-biochar composite exhibited a better regeneration capacity. In the results of leaching experiment, the highest amount of dye solution removed by iron composites produced at 300 and 600 ̊C (100%) after three stages of leaching, and the lowest removal percentage was for copper produced at 300 ̊C (56.1%). Adsorption Anionic contaminant Biochar-metal composite Leaching 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. 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. 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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-8457392","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":582560530,"identity":"0682e775-a447-45d0-85d4-ecf8459ea3d7","order_by":0,"name":"Hanyeh Sepahvand","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Hanyeh","middleName":"","lastName":"Sepahvand","suffix":""},{"id":582560531,"identity":"ce6d8a96-f5d4-4d9e-b1a6-d38c47bf20b5","order_by":1,"name":"Fardin Sadeghzadeh","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA3ElEQVRIiWNgGAWjYBAC9gYGBokEMJP5AJCQkCGohecAXAsbiJLgIU4LlGkAJglrYT/78MbDHQyJ28XOfH51o8aCh4H98NENeLXwpBtbJJ5hSNw5O3ebdc4xoMN40tJu4NNiz5DGJpHYxpC44XbuNuMcNqAWCR4zvFp4+J/BtOQ8M875R4wWCbgtOcyPc9uI0vKM2SKxTcJ45+w0M+bcPgkeNkJ+4eFPY7z5s81Gdrt08uPPOd/q5PjZDx/DqwUKJBiAkcIGjiA2IpRDAFAL8weiVY+CUTAKRsGIAgAVyUKDxHffiwAAAABJRU5ErkJggg==","orcid":"","institution":"University of Mazandaran","correspondingAuthor":true,"prefix":"","firstName":"Fardin","middleName":"","lastName":"Sadeghzadeh","suffix":""},{"id":582560532,"identity":"a0f3453b-31ff-45fc-9761-b8e8384d38b5","order_by":2,"name":"Bahi Jalili","email":"","orcid":"","institution":"University of Mazandaran","correspondingAuthor":false,"prefix":"","firstName":"Bahi","middleName":"","lastName":"Jalili","suffix":""},{"id":582560533,"identity":"7e700117-24fb-45de-93ac-c9935d2b7e75","order_by":3,"name":"Maedeh Parichehre","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Maedeh","middleName":"","lastName":"Parichehre","suffix":""}],"badges":[],"createdAt":"2025-12-26 19:53:06","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8457392/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8457392/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":104808173,"identity":"cecd8c2c-db70-4e93-a7f5-1af59c2d42ec","added_by":"auto","created_at":"2026-03-17 12:25:23","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":758129,"visible":true,"origin":"","legend":"","description":"","filename":"finalmodified22.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8457392/v1_covered_d18526eb-d94a-445c-8904-48f2b2b12d47.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"The assessment of biochar-metal composite in removal of direct blue-71 from aqueous solution","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":"Adsorption, Anionic contaminant, Biochar-metal composite, Leaching","lastPublishedDoi":"10.21203/rs.3.rs-8457392/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8457392/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eIn this study, biochar, metal-coated biochar, and biochar-metal composites of different metals were prepared using rice straw as the raw material. Three elements, iron, copper, and zinc, were selected for preparing the adsorbents for further tests. In this study, we used Direct Blue 71(DB71) as an anionic pollutant sample, which is abundant in the study region. The effects of pH (3.0\u0026ndash;9.0), adsorption time (0-420 min), and sorbent dosage (2.5 25 g L\u003csup\u003e-1\u003c/sup\u003e) on the removal of DB71 were investigated, and a regeneration experiment was performed. In order to compare the effect of temperature, a leaching experiment was performed using biochar and metal-biochar composites produced at two temperatures (300 and 600\u0026deg;C) as adsorbents to remove DB71 from water. The results showed that the maximum adsorption capacity of DB71 was obtained at 180 min, pH 6, and dosage of 12.5 g L\u003csup\u003e-1\u003c/sup\u003e. The Fe-biochar composite exhibited a better regeneration capacity. 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