Thermodynamics of the $\alpha$-FeOOH (goethite)-ScOOH solid solution

Thermodynamics of the $\alpha$-FeOOH (goethite)-ScOOH solid 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Article Thermodynamics of the $\alpha$-FeOOH (goethite)-ScOOH solid solution Juraj Majzlan This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4550357/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 02 Oct, 2024 Read the published version in Physics and Chemistry of Minerals → Version 1 posted 10 You are reading this latest preprint version Abstract Scandium (Sc) is a rare element that finds uses in modern technologies. Thermodynamic properties of Sc phases could help in the development of innovative technologies to extract Sc from mining waste. In this work, we investigated the FeOOH-ScOOH solid solution with the goethite structure. The end members and five intermediate compositions were synthesized and characterized. The lattice parameters show that the solid solution is non-ideal, with complex behavior induced by the Fe-Sc substitution. The excess unit-cell volume deviates negatively for the Sc-rich region, and positively for the Fe-rich region from the ideal behavior (Vegard's law). Enthalpies of dissolution were determined by acid-solution calorimetry in 5 mol \(\cdot\) dm \(^{-3}\) HCl at T = 343.15 K. Enthalpies of mixing ( $ \Delta_{mix}H $ ), calculated from the experimental data, are small and positive. The available data allow for fitting the data as $ \Delta_{mix}H = W x (1-x) $ , with the mixing parameter $ W = 15.2\pm $ 1.0 kJ $ \cdot $ mol $ ^{-1} $ . Using $ \Delta_fG^o $ of ScOOH from earlier literature, we calculated a Lippmann diagram that shows that Sc should strongly partition into the aqueous phase upon goethite precipitation. The thermodynamic conclusions disagree with field observations that Sc is primarily harbored by goethite in lateritic profiles. It seems that under weathering conditions, adsorption of Sc $ ^{3+} $ and kinetic hindrance to exsolution prevail over thermodynamic driving forces. goethite ScOOH thermodynamics solid solution mixing enthalpies Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Published Journal Publication published 02 Oct, 2024 Read the published version in Physics and Chemistry of Minerals → Version 1 posted Reviews received at journal 02 Jul, 2024 Reviews received at journal 26 Jun, 2024 Reviewers agreed at journal 10 Jun, 2024 Reviewers agreed at journal 10 Jun, 2024 Reviewers agreed at journal 10 Jun, 2024 Reviewers agreed at journal 10 Jun, 2024 Reviewers invited by journal 09 Jun, 2024 Editor assigned by journal 09 Jun, 2024 Submission checks completed at journal 09 Jun, 2024 First submitted to journal 08 Jun, 2024 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. 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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-4550357","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":317170193,"identity":"5ec360f3-3ab1-4bc7-aac8-dd57de428e58","order_by":0,"name":"Juraj Majzlan","email":"data:image/png;base64,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","orcid":"","institution":"Friedrich Schiller University","correspondingAuthor":true,"prefix":"","firstName":"Juraj","middleName":"","lastName":"Majzlan","suffix":""}],"badges":[],"createdAt":"2024-06-08 11:21:15","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4550357/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4550357/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s00269-024-01298-1","type":"published","date":"2024-10-02T15:58:29+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":66097526,"identity":"1a908f64-ca59-465e-a00d-4b3bc34b2ff8","added_by":"auto","created_at":"2024-10-07 16:14:28","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":600795,"visible":true,"origin":"","legend":"","description":"","filename":"FeOOHScOOHMajzlan.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4550357/v1_covered_a422d420-4787-403b-b9e9-14e118e44340.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Thermodynamics of the $\\alpha$-FeOOH (goethite)-ScOOH solid solution","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"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":"physics-and-chemistry-of-minerals","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"pcmi","sideBox":"Learn more about [Physics and Chemistry of Minerals](http://link.springer.com/journal/269)","snPcode":"269","submissionUrl":"https://submission.nature.com/new-submission/269/3","title":"Physics and Chemistry of Minerals","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"goethite, ScOOH, thermodynamics, solid solution, mixing enthalpies","lastPublishedDoi":"10.21203/rs.3.rs-4550357/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4550357/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e Scandium (Sc) is a rare element that finds uses in modern technologies. Thermodynamic properties of Sc phases could help in the development of innovative technologies to extract Sc from mining waste. In this work, we investigated the FeOOH-ScOOH solid solution with the goethite structure. The end members and five intermediate compositions were synthesized and characterized. The lattice parameters show that the solid solution is non-ideal, with complex behavior induced by the Fe-Sc substitution. The excess unit-cell volume deviates negatively for the Sc-rich region, and positively for the Fe-rich region from the ideal behavior (Vegard's law). Enthalpies of dissolution were determined by acid-solution calorimetry in 5 mol\u003cspan class=\"InlineEquation\"\u003e \u003cspan class=\"mathinline\"\u003e \\(\\cdot\\) \u003c/span\u003e \u003c/span\u003edm\u003cspan class=\"InlineEquation\"\u003e \u003cspan class=\"mathinline\"\u003e \\(^{-3}\\) \u003c/span\u003e \u003c/span\u003e HCl at \u003cem\u003eT\u003c/em\u003e = 343.15 K. Enthalpies of mixing (\u003cspan\u003e$\u003c/span\u003e\\Delta_{mix}H\u003cspan\u003e$\u003c/span\u003e), calculated from the experimental data, are small and positive. The available data allow for fitting the data as \u003cspan\u003e$\u003c/span\u003e\\Delta_{mix}H = W x (1-x)\u003cspan\u003e$\u003c/span\u003e, with the mixing parameter \u003cspan\u003e$\u003c/span\u003eW = 15.2\\pm\u003cspan\u003e$\u003c/span\u003e1.0 kJ\u003cspan\u003e$\u003c/span\u003e\\cdot\u003cspan\u003e$\u003c/span\u003emol\u003cspan\u003e$\u003c/span\u003e^{-1}\u003cspan\u003e$\u003c/span\u003e. Using \u003cspan\u003e$\u003c/span\u003e\\Delta_fG^o\u003cspan\u003e$\u003c/span\u003e of ScOOH from earlier literature, we calculated a Lippmann diagram that shows that Sc should strongly partition into the aqueous phase upon goethite precipitation. The thermodynamic conclusions disagree with field observations that Sc is primarily harbored by goethite in lateritic profiles. It seems that under weathering conditions, adsorption of Sc\u003cspan\u003e$\u003c/span\u003e^{3+}\u003cspan\u003e$\u003c/span\u003e and kinetic hindrance to exsolution prevail over thermodynamic driving forces.\u003c/p\u003e","manuscriptTitle":"Thermodynamics of the $\\alpha$-FeOOH (goethite)-ScOOH solid solution","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-06-24 08:47:51","doi":"10.21203/rs.3.rs-4550357/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"editorInvitedReview","content":"","date":"2024-07-02T15:32:12+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2024-06-26T05:00:43+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"328723605641660424547254667904651042610","date":"2024-06-11T03:27:58+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"171249632165749182354469676633812213845","date":"2024-06-10T18:39:25+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"114731298350846692774850893587811928175","date":"2024-06-10T13:52:55+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"127208925070390608471842778823054385866","date":"2024-06-10T04:19:56+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-06-10T00:51:39+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-06-10T00:32:29+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2024-06-09T07:08:38+00:00","index":"","fulltext":""},{"type":"submitted","content":"Physics and Chemistry of Minerals","date":"2024-06-08T11:18:30+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"physics-and-chemistry-of-minerals","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"pcmi","sideBox":"Learn more about [Physics and Chemistry of Minerals](http://link.springer.com/journal/269)","snPcode":"269","submissionUrl":"https://submission.nature.com/new-submission/269/3","title":"Physics and Chemistry of Minerals","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"d6e82187-7201-4698-a4d5-701d14ebc7ed","owner":[],"postedDate":"June 24th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2024-10-07T16:09:37+00:00","versionOfRecord":{"articleIdentity":"rs-4550357","link":"https://doi.org/10.1007/s00269-024-01298-1","journal":{"identity":"physics-and-chemistry-of-minerals","isVorOnly":false,"title":"Physics and Chemistry of Minerals"},"publishedOn":"2024-10-02 15:58:29","publishedOnDateReadable":"October 2nd, 2024"},"versionCreatedAt":"2024-06-24 08:47:51","video":"","vorDoi":"10.1007/s00269-024-01298-1","vorDoiUrl":"https://doi.org/10.1007/s00269-024-01298-1","workflowStages":[]},"version":"v1","identity":"rs-4550357","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4550357","identity":"rs-4550357","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}