Abstract
This study investigated the removal of toxic Malachite Green (MG) dye from aqueous solution using a nanocomposite of TiO₂ loaded on functionalized multi-walled carbon nanotubes (TiO₂/f-MWCNT). The nanocomposite was synthesized via a hydrothermal method and characterized using XRD, FESEM, FTIR, BET, and EDS. The optimal adsorption conditions were determined as pH = 8, adsorbent dose of 0.005 g, equilibrium time of 10 min, and temperature of 293 K. Under these conditions, the maximum adsorption capacity reached 38.61 mg/g with a removal efficiency exceeding 95%. Kinetic data showed an excellent fit to the pseudo-second-order model (R2 = 0.99), indicating a chemisorption-controlled process. The equilibrium adsorption behavior was well described by the Langmuir-2 isotherm model (R2 = 0.99), confirming monolayer formation on a homogeneous surface. Additionally, the Freundlich, Temkin, and Elovich models also showed favorable fitting (R2 ≥ 0.98), suggesting a combined physical–chemical adsorption mechanism on a heterogeneous surface. The adsorbent was effectively regenerated with a 1 M NaOH solution, achieving 99% recovery. These results demonstrate the rapid and efficient performance of TiO₂/f-MWCNT as a promising adsorbent for the treatment of wastewater containing cationic dyes.
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The authors declare that the data supporting the findings of this study are available within the paper [and its supplementary information files], a request for more detailed data should be send to the corresponding authors with the permission of all authors.
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Acknowledgements
The authors thanks Behbahan Khatam Alanbia university of technology for financial support (Grant numbers, 3.2.8124).
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Fereshteh Jomardani: Investigation, Methodology, Formal analysis. Reza shakeri: Supervision, Data curation, Investigation, Writing—review & editing. Raziyeh Akbarzadeh: Supervision, Software, Formal analysis, Methodology, Writing—review & editing, Writing—original draft, Project administration, Investigation, Data curation, Validation, Resources, Visualization, Funding acquisition. Syamak Nasiri Kokhdan: Project administration, Software, Writing—review & editing, Visualization, Conceptualization, Data curation, Visualization, Funding acquisition.
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Jomardani, F., shakeri, R., Akbarzadeh, R. et al. Adsorption kinetics and isotherms of malachite green removal from aqueous solution using TiO2 loaded on f-MWCNTs nanocomposite. Sci Rep (2026). https://doi.org/10.1038/s41598-026-38582-9
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DOI: https://doi.org/10.1038/s41598-026-38582-9
