Adsorption of acid red 14 from aqueous solutions by ZnO-tyre: kinetics, isotherms, and mechanisms

ABSTRACT

This research evaluated the effectiveness of using zinc oxide-waste tyre (ZnO-WT) for the adsorptive removal of the harmful acid red 14 azo dye (AR14 AzD) from polluted water. The synthesised materials were characterised using FT-IR, XRD, FESEM, EDX-map, and pH_pzc analyses. Examination of key operational factors confirmed that the adsorptive removal rate of AzD reached 90.09% under the conditions of pH= 3, ZnO-WT= 1 g L^{− 1}, [AR14]₀= 20 mg L^{− 1}, and T= 298 K within 2 hours. The pseudo-second-order (PSO) (R²= 0.9981) and Langmuir (R²= 0.9984) kinetic and isotherm models fitted well with all AzD adsorption data. Notably, the maximum adsorption capacity (q_m) of ZnO-WT towards AR14 was found to be 204.082 mg g^{− 1} at T= 298 K. Moreover, adsorption thermodynamics revealed that the AR14 uptake process was both endothermic (+ΔH${ }^{\circ }$) and spontaneous (−ΔG${ }^{\circ }$). Reusability tests demonstrated that the nanocomposites (NCs) were sufficiently stable and reusable. The production cost of the ZnO-WT NCs on a laboratory scale was 0.0886 USD per 8 g, while the cost associated with AR14 adsorptive removal was 0.0576 USD, making it an economical option for large-scale industrial use. These results suggest that waste tyres could be repurposed to produce a new class of carbon materials, with ZnO-WT effectively serving as a low-cost and environmentally friendly adsorbent for removing AR14 dye from aqueous solutions.

KEYWORDS:

• Acid red 14
• adsorption
• ZnO-WT NCs
• Kinetic
• equilibrium
• cost analysis

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/03067319.2024.2384648

Acknowledgments

This research was accepted by the research ethics committee of Guilan University of Medical Sciences ((GUMS), No: IR.GUMS.REC.1401.462) as MSc student’s thesis of Mobarakeh Hasanpour. We extend our sincere appreciation to the Research Center of Health and Environment at GUMS, Rasht, Iran, for their invaluable support throughout this study.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author contribution

Mobarakeh Hasanpour: Data curation, Writing-original draft, Methodology, Software and Formal analysis. Mehdi Shirzad-Siboni: Advisor, Design of the project, Investigation, Data curation, Writing- review & editing, Software, Formal analysis, Methodology, responding to reviewers and revising the manuscript. Kobra Ayagh: Writing-review & editing, Methodology, Software and Formal analysis, responding to reviewers and revising the manuscript. Azita Mohagheghian: Supervisor, Design of the project, Investigation, Data curation, Writing- review & editing, Software, Formal analysis, Methodology, responding to reviewers and revising the manuscript.

Data availability statement

The datasets utilised and/or analysed during the current research are available from the corresponding author on reasonable request.