Impact of Hardness on the Interaction of Zn(Ii) with a Fibrous Biosorbent, Panicum Maximum Dried Leaves

Impact of Hardness on the Interaction of Zn(Ii) with a Fibrous Biosorbent, Panicum Maximum Dried Leaves | 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 Impact of Hardness on the Interaction of Zn(Ii) with a Fibrous Biosorbent, Panicum Maximum Dried Leaves Suranga Premachandra, Mishantha Kanishka, Namal Priyantha This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8584467/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 Environmental pollution is becoming increasingly problematic due to industrial expansion and population growth. As industrial effluents release pollutants harmful to various environmental compartments, including surface water, their removal from contaminated water using low-cost, natural adsorbents has gained much attention. This study focuses on the investigation of adsorption characteristics of dried leaves of Panicum maximum , a fibrous biosorbent, toward Zn(II) from water and the effect of water hardness on Zn(II)-biosorbent interaction, a novel aspect of biosorption research. The presence of functional groups in the biosorbent, determined by Fourier transform infrared spectroscopy, would promote its attraction toward Zn(II), and further, the availability of vacant sites, determined by scanning electron microscopy, provides strong evidence for trapping Zn(II). Interaction of Zn(II) on the biosorbent obeys the Langmuir adsorption isotherm better than the Freundlich adsorption isotherm according to linear regression analysis, indicating the initial monolayer coverage of the adsorbate. The maximum adsorption capacity determined under the optimum experimental conditions of shaking time, settling time, solution pH and adsorbent dosage is 9.9×10 3 mg kg − 1 , which is comparable to many other adsorption systems. The interaction between Zn(II) and the biosorbent is so strong that the extent of removal is not much influenced by variation of hardness of the medium up to 100 mg L − 1 CaCO 3 hardness and that a relatively high pseudo second order rate constant results in with a regression coefficient of 0.999. Therefore, this fibrous biosorbent has great potential for scaling up the proposed methodology for remediation of Zn(II) from contaminated industrial effluents. Environmental pollution hardness isotherm kinetics monolayer Full Text 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. 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-8584467","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":574425549,"identity":"0d12d4df-22c5-4701-9966-b2a14a9f3f2c","order_by":0,"name":"Suranga Premachandra","email":"","orcid":"","institution":"University of Peradeniya Postgraduate Institute of Science","correspondingAuthor":false,"prefix":"","firstName":"Suranga","middleName":"","lastName":"Premachandra","suffix":""},{"id":574425550,"identity":"f2d866c3-5fcb-4dac-a94e-7e65e42b2d96","order_by":1,"name":"Mishantha Kanishka","email":"","orcid":"","institution":"University of 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Leaves\u003c/p\u003e","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":"Environmental pollution, hardness, isotherm, kinetics, monolayer","lastPublishedDoi":"10.21203/rs.3.rs-8584467/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8584467/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eEnvironmental pollution is becoming increasingly problematic due to industrial expansion and population growth. As industrial effluents release pollutants harmful to various environmental compartments, including surface water, their removal from contaminated water using low-cost, natural adsorbents has gained much attention. This study focuses on the investigation of adsorption characteristics of dried leaves of \u003cem\u003ePanicum maximum\u003c/em\u003e, a fibrous biosorbent, toward Zn(II) from water and the effect of water hardness on Zn(II)-biosorbent interaction, a novel aspect of biosorption research. The presence of functional groups in the biosorbent, determined by Fourier transform infrared spectroscopy, would promote its attraction toward Zn(II), and further, the availability of vacant sites, determined by scanning electron microscopy, provides strong evidence for trapping Zn(II). Interaction of Zn(II) on the biosorbent obeys the Langmuir adsorption isotherm better than the Freundlich adsorption isotherm according to linear regression analysis, indicating the initial monolayer coverage of the adsorbate. The maximum adsorption capacity determined under the optimum experimental conditions of shaking time, settling time, solution pH and adsorbent dosage is 9.9\u0026times;10\u003csup\u003e3\u003c/sup\u003e mg kg\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e\u003csub\u003e,\u003c/sub\u003e which is comparable to many other adsorption systems. The interaction between Zn(II) and the biosorbent is so strong that the extent of removal is not much influenced by variation of hardness of the medium up to 100 mg L\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e CaCO\u003csub\u003e3\u003c/sub\u003e hardness and that a relatively high pseudo second order rate constant results in with a regression coefficient of 0.999. Therefore, this fibrous biosorbent has great potential for scaling up the proposed methodology for remediation of Zn(II) from contaminated industrial effluents.\u003c/p\u003e","manuscriptTitle":"Impact of Hardness on the Interaction of Zn(Ii) with a Fibrous Biosorbent, Panicum Maximum Dried Leaves","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-01-16 17:13:03","doi":"10.21203/rs.3.rs-8584467/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":"408e2abd-a419-4f2a-b64a-41f4762441c9","owner":[],"postedDate":"January 16th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-01-22T21:22:29+00:00","versionOfRecord":[],"versionCreatedAt":"2026-01-16 17:13:03","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8584467","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8584467","identity":"rs-8584467","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}