Development of complex technology for pyrite-cobalt concentrate processing by sodium carbonate-carbon reductive smelting

Development of complex technology for pyrite-cobalt concentrate processing by sodium carbonate-carbon reductive smelting | 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 Article Development of complex technology for pyrite-cobalt concentrate processing by sodium carbonate-carbon reductive smelting T. A. Chepushtanova, A. Altmyshbayeva, Y. Merkibayev, K. K. Mamyrbayeva, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9123065/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 10 You are reading this latest preprint version Abstract An integrated pyro–hydrometallurgical technology for the processing of pyrite-cobalt concentrates has been developed based on sodium carbonate–carbon reductive smelting followed by aqueous treatment of the slag–matte melt. Thermodynamic modeling of the Fe–Ni–Co–Cu–O–S system demonstrated that at 1450–1500°C the Na₂CO₃–C system forms a strongly reducing environment due to CO generation and sulfur fixation as Na₂S. It was established that this mechanism simultaneously decreases oxygen and sulfur potentials, shifting sulfide systems into the metallic stability region of Me–O–S diagrams. New experimental data were obtained on the distribution of Ni, Co, Fe, Cu, and Zn between metallic alloy, slag–matte melt, and volatilized phases during soda-reductive smelting of synthetic and industrial sulfide materials. The optimal smelting parameters were determined as 7–8 wt.% carbon and 130–140% Na₂CO₃ of the theoretical requirement for Fe, Ni, and Co (180 % for Cu). Under these conditions, recoveries reached up to 96.5% Fe, 94–96% Ni, 97.5–99% Co, and 93.2% Cu. For Zn-bearing sulfide cakes, selective separation was observed: Ni, Co, and Fe were concentrated in a metallic alloy, whereas Zn was transferred predominantly to dust (up to 82.3%). The resulting alloy (Ni ≈ 26%, Co ≈ 42%, Fe ≈ 30%, S ≈ 0.074%) forms a homogeneous γ-(Ni,Co,Fe) solid solution suitable as an intermediate material for alloyed steels and functional alloys. Physical sciences/Chemistry Physical sciences/Materials science Critical raw materials Mining waste Cobalt Zinc Hydrometallurgy Pyrometallurgy Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Revision Version 1 posted Editorial decision: Revision requested 20 Apr, 2026 Reviews received at journal 14 Apr, 2026 Reviewers agreed at journal 14 Apr, 2026 Reviewers agreed at journal 13 Apr, 2026 Reviews received at journal 02 Apr, 2026 Reviewers agreed at journal 26 Mar, 2026 Reviewers invited by journal 24 Mar, 2026 Editor assigned by journal 24 Mar, 2026 Submission checks completed at journal 21 Mar, 2026 First submitted to journal 21 Mar, 2026 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-9123065","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":611461671,"identity":"0b3bf4d2-9cfa-4483-8504-2a6319cd9af0","order_by":0,"name":"T. A. 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Thermodynamic modeling of the Fe–Ni–Co–Cu–O–S system demonstrated that at 1450–1500°C the Na₂CO₃–C system forms a strongly reducing environment due to CO generation and sulfur fixation as Na₂S. It was established that this mechanism simultaneously decreases oxygen and sulfur potentials, shifting sulfide systems into the metallic stability region of Me–O–S diagrams. New experimental data were obtained on the distribution of Ni, Co, Fe, Cu, and Zn between metallic alloy, slag–matte melt, and volatilized phases during soda-reductive smelting of synthetic and industrial sulfide materials. The optimal smelting parameters were determined as 7–8 wt.% carbon and 130–140% Na₂CO₃ of the theoretical requirement for Fe, Ni, and Co (180 % for Cu). Under these conditions, recoveries reached up to 96.5% Fe, 94–96% Ni, 97.5–99% Co, and 93.2% Cu. For Zn-bearing sulfide cakes, selective separation was observed: Ni, Co, and Fe were concentrated in a metallic alloy, whereas Zn was transferred predominantly to dust (up to 82.3%). The resulting alloy (Ni ≈ 26%, Co ≈ 42%, Fe ≈ 30%, S ≈ 0.074%) forms a homogeneous γ-(Ni,Co,Fe) solid solution suitable as an intermediate material for alloyed steels and functional alloys.\u003c/p\u003e","manuscriptTitle":"Development of complex technology for pyrite-cobalt concentrate processing by sodium carbonate-carbon reductive smelting","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-26 17:30:47","doi":"10.21203/rs.3.rs-9123065/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-04-20T05:05:16+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-14T11:45:48+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"123993183852374924961510501851303282885","date":"2026-04-14T04:08:09+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"316080359486096543920308342605395729173","date":"2026-04-13T05:18:17+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-02T06:01:12+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"145885918972071210512916741440216862518","date":"2026-03-26T14:59:32+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-03-24T14:41:47+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-24T07:33:50+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-03-21T08:35:34+00:00","index":"","fulltext":""},{"type":"submitted","content":"Scientific Reports","date":"2026-03-21T08:29:14+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"a9969bbb-c3ca-4e80-83a9-ded5546e3527","owner":[],"postedDate":"March 26th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"in-revision","subjectAreas":[{"id":65060906,"name":"Physical sciences/Chemistry"},{"id":65060907,"name":"Physical sciences/Materials science"}],"tags":[],"updatedAt":"2026-05-15T07:11:14+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-26 17:30:47","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9123065","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9123065","identity":"rs-9123065","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}