Biosourced choline-functionalized sawdust for dual dye removal: ion-exchange versus multifactorial adsorption mechanisms

Biosourced choline-functionalized sawdust for dual dye removal: ion-exchange versus multifactorial adsorption mechanisms | 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 Biosourced choline-functionalized sawdust for dual dye removal: ion-exchange versus multifactorial adsorption mechanisms Meriem Bendjelloul, El Hadj Elandaloussi, Fatima Zahra Benhachem, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9451824/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 14 You are reading this latest preprint version Abstract Choline-functionalized sawdust (CFS) was developed as a sustainable biosorbent for the removal of structurally distinct dyes. Adsorption studies revealed dual mechanistic pathways: Indigo Carmine uptake is dominated by sulfonate–ammonium ion exchange, producing rapid kinetics, and exothermic thermodynamics, whereas Methylene Blue removal proceeds through multifactorial interactions, resulting in slower kinetics, and entropy-driven adsorption. Langmuir isotherms yielded q max values of 125 mg g ‒1 for IC and 43.1 mg g ‒1 for MB, while complementary nonlinear models highlighted the monomechanistic nature of IC adsorption versus the heterogeneous, energetically variable uptake of MB. Adsorption was largely insensitive to ionic strength, underscoring robustness under saline conditions. Regeneration experiments confirmed recyclability, with IC uptake reversed by NaOH and MB restored by NaCl. Overall, CFS emerges as a cost-effective, bio-based adsorbent derived from lignocellulosic waste, combining dual adsorption capacity, ionic strength resilience, and regeneration efficiency, making it a promising candidate for sustainable wastewater treatment. Lignocellulosic waste valorization Dye adsorption Ion-exchange mechanism Multifactorial interactions Ionic strength resilience Sustainable wastewater treatment Full Text Additional Declarations No competing interests reported. Supplementary Files SupplementaryData.pdf Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 04 May, 2026 Reviews received at journal 30 Apr, 2026 Reviewers agreed at journal 28 Apr, 2026 Reviewers agreed at journal 27 Apr, 2026 Reviews received at journal 25 Apr, 2026 Reviewers agreed at journal 23 Apr, 2026 Reviews received at journal 22 Apr, 2026 Reviewers agreed at journal 22 Apr, 2026 Reviewers agreed at journal 22 Apr, 2026 Reviewers agreed at journal 22 Apr, 2026 Reviewers invited by journal 20 Apr, 2026 Editor assigned by journal 20 Apr, 2026 Submission checks completed at journal 19 Apr, 2026 First submitted to journal 17 Apr, 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. 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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-9451824","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":630213303,"identity":"3bda416b-da39-47ba-a3f3-0e4efe6bf249","order_by":0,"name":"Meriem Bendjelloul","email":"","orcid":"","institution":"University of Relizane","correspondingAuthor":false,"prefix":"","firstName":"Meriem","middleName":"","lastName":"Bendjelloul","suffix":""},{"id":630213304,"identity":"db6b62da-d342-477c-9b32-ff7a2cd04704","order_by":1,"name":"El Hadj 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