Enhancing Cs retention in superabsorbent polymers via selective Ca removal by CO2 bubbling in fly-ash aqueous systems

Enhancing Cs retention in superabsorbent polymers via selective Ca removal by CO2 bubbling in fly-ash aqueous systems | 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 Enhancing Cs retention in superabsorbent polymers via selective Ca removal by CO2 bubbling in fly-ash aqueous systems Shogo Higaki, Toru Oishi This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9400335/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, we aimed to safely treat fly ash generated during the incineration-based volume reduction of 137 Cs-contaminated waste from the Fukushima Daiichi Nuclear Power Plant accident by applying SAP in the fly-ash washing process. To enhance the Cs⁺ retention capacity of SAP, we investigated the removal of the interfering element Ca from fly-ash aqueous solutions by inducing CaCO 3 precipitation via CO 2 bubbling. When CO 2 bubbling adjusted the pH of the solution to an appropriate range, Ca 2+ concentrations decreased through CaCO 3 precipitation, thereby decreasing the distribution coefficient for Ca and enhancing that for Cs. This method is advantageous because it does not require chemical modification of SAP and avoids increasing the electrolyte concentration, which would otherwise reduce SAP water-absorption capacity. superabsorbent polymer cesium calcium distribution coefficient fly ash bubbling Full Text Additional Declarations No competing interests reported. Supplementary Files Supplementaryinformation.pdf 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-9400335","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":631767801,"identity":"50556e88-1c3e-4ba3-840c-54983dbb969a","order_by":0,"name":"Shogo Higaki","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA/UlEQVRIiWNgGAWjYDACCRBRwcAD5SZAaR6sipG0nIEqOUC0FsY2KAehBQ+Qn918+MXHefdk+Bt4DJg/VKQl9jMwP/zAIHMHpxaDO8fSLGduK+aROMBjwHDgTE7izAY2YwkGnme4tUjkmBnzbksAqucx/3GwrSJxwwEGM6BfDuN22AyQljlgLQYMEC3s3/BqYbiRY/yYtwGuJQeohQe/LQY30tIYZxxL4JE4zFbAcOZMmvHMZp5iiQQ8fpGfkXz4w4eaBHv+9uYNDBUVybL97O0bP3zswR1iQMAGjk0GZgjPsQHESOw5gE8L8wdknj2E+oFXyygYBaNgFIwsAAC2FlCIw5RgBwAAAABJRU5ErkJggg==","orcid":"","institution":"The University of Tokyo","correspondingAuthor":true,"prefix":"","firstName":"Shogo","middleName":"","lastName":"Higaki","suffix":""},{"id":631767804,"identity":"86c4ab74-6607-4e64-bcda-6b00dd74935d","order_by":1,"name":"Toru Oishi","email":"","orcid":"","institution":"Nippon Steel Blast Furnace Slag Cement Co. 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To enhance the Cs⁺ retention capacity of SAP, we investigated the removal of the interfering element Ca from fly-ash aqueous solutions by inducing CaCO\u003csub\u003e3\u003c/sub\u003e precipitation via CO\u003csub\u003e2\u003c/sub\u003e bubbling. When CO\u003csub\u003e2\u003c/sub\u003e bubbling adjusted the pH of the solution to an appropriate range, Ca\u003csup\u003e2+\u003c/sup\u003e concentrations decreased through CaCO\u003csub\u003e3\u003c/sub\u003e precipitation, thereby decreasing the distribution coefficient for Ca and enhancing that for Cs. 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