Activated Rice Husk Ash: A Sustainable and High-Capacity Adsorbent for the Remediation of Carbol Fuchsin Dye from Aqueous Effluents

Activated Rice Husk Ash: A Sustainable and High-Capacity Adsorbent for the Remediation of Carbol Fuchsin Dye from Aqueous Effluents | 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 Activated Rice Husk Ash: A Sustainable and High-Capacity Adsorbent for the Remediation of Carbol Fuchsin Dye from Aqueous Effluents Asmit Patel, Adarsh Pratap Singh, Anshika Sharma, Priya Tiwari, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8364635/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 The discharge of persistent synthetic dyes, such as Carbol Fuchsin (CF), from textile and related industries constitutes a significant environmental and public health concern because oftheir toxicity and resistance to natural degradation. This study presents the development and application of a low-cost, sustainable adsorbent—activated carbon derived from rice husk ash (ARHA)—for the efficient removal of CF from contaminated water. The adsorbent was characterized using FT-IR, SEM-EDX, XRD, and zeta potential analysis, revealing a mesoporous, amorphous structure with a specific surface area of 50–270 m²/g and a point of zero charge (pHpzc) at 8.3. Systematic batch adsorption studies were conducted to optimize the process parameters, achieving a maximum removal efficiency of >96% at an adsorbent dosage of 0.08 g/50 mL, contact time of 150 min, and pH 9.0. The adsorption kinetics were best described by the pseudo-second-order model, indicating that chemisorption was the rate-limiting step. The equilibrium isotherm data were well-fitted by the Langmuir model, confirming monolayer adsorption with an exceptionally high maximum capacity of 205.24 mg/g. Thermodynamic analysis (negative ΔG° and ΔH°) established the process as spontaneous and exothermic. The findings demonstrate that ARHA, an agricultural waste derivative, is a highly effective, eco-friendly, and economically viable material for the advanced treatment of dye-laden industrial wastewater, offering a promising alternative to conventional remediation methods. Full Text Additional Declarations No competing interests reported. Supplementary Files Supplimentry.docx Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 19 Jan, 2026 Reviews received at journal 19 Jan, 2026 Reviews received at journal 15 Jan, 2026 Reviews received at journal 13 Jan, 2026 Reviews received at journal 10 Jan, 2026 Reviews received at journal 10 Jan, 2026 Reviewers agreed at journal 06 Jan, 2026 Reviewers agreed at journal 03 Jan, 2026 Reviewers agreed at journal 03 Jan, 2026 Reviewers agreed at journal 02 Jan, 2026 Reviewers invited by journal 01 Jan, 2026 Editor assigned by journal 21 Dec, 2025 Submission checks completed at journal 21 Dec, 2025 First submitted to journal 15 Dec, 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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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-8364635","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":560438374,"identity":"7e2327c6-f380-49da-b005-89fce66e40fd","order_by":0,"name":"Asmit 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Thermodynamic analysis (negative ΔG° and ΔH°) established the process as spontaneous and exothermic. 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