Leaching Behavior and Kinetics of Gallium with Organic Acids: Foundations for E-Waste Recovery and Bioleaching Applications

Leaching Behavior and Kinetics of Gallium with Organic Acids: Foundations for E-Waste Recovery and Bioleaching Applications | 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 Leaching Behavior and Kinetics of Gallium with Organic Acids: Foundations for E-Waste Recovery and Bioleaching Applications Aylin Nur Erkmen, Roland Ulber, Thomas Jüstel, Mirjam Altendorfner This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7030914/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 02 Dec, 2025 Read the published version in Scientific Reports → Version 1 posted 13 You are reading this latest preprint version Abstract This study systematically concerns the leaching behavior and dissolution kinetics of gallium (Ga). The objective was to identify sustainable leaching agents by incorporating organic acid reagents. Using a novel approach involving pH-adjusted experiments, the findings elucidated the dissolution behavior, delineating acidolysis and complexolysis. The screening results demonstrated the efficacy of oxalic acid (10 mM), which extracted 1105.2 ± 61.4 mg/L of Ga at pH 1.2. Dissolution kinetics based on the shrinking core model (SCM) revealed a synergistic mechanism governed by film diffusion and surface chemical reaction control, with chemical reaction control dominating at higher temperatures. One-factor-at-a-time (OFAT) experiments clarified the influence of experimental parameters on Ga leaching yield. In addition, the Box-Behnken design (BBD) was employed to evaluate parameter interactions, confirming the significance of the process parameters, including interaction terms, while characterizing the model in terms of a quadratic expression. Under optimized conditions: 710.55 mM acid concentration, a reaction temperature of 84.5°C, and a solid loading of 50 g/L, 37% of Ga was effectively extracted within 3.2 hours. These findings underscore the selectivity and operational compatibility of oxalic acid compared to conventional leaching agents, emphasizing its promising integration into biogenic production pathways and sustainable closed-loop gallium recovery processes. Physical sciences/Chemistry Earth and environmental sciences/Environmental sciences critical metals gallium metal leaching sustainable chemistry oxalic acid Full Text Additional Declarations No competing interests reported. Supplementary Files supplementary.pdf Cite Share Download PDF Status: Published Journal Publication published 02 Dec, 2025 Read the published version in Scientific Reports → Version 1 posted Editorial decision: Revision requested 11 Sep, 2025 Reviews received at journal 01 Sep, 2025 Reviewers agreed at journal 17 Aug, 2025 Reviewers agreed at journal 17 Aug, 2025 Reviewers agreed at journal 17 Aug, 2025 Reviews received at journal 12 Aug, 2025 Reviewers agreed at journal 04 Aug, 2025 Reviewers agreed at journal 15 Jul, 2025 Reviewers invited by journal 08 Jul, 2025 Editor invited by journal 08 Jul, 2025 Editor assigned by journal 04 Jul, 2025 Submission checks completed at journal 03 Jul, 2025 First submitted to journal 02 Jul, 2025 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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