Research Article Published: July 25, 2025 Volume 1, Issue 5

Sustainable Remediation of Synthetic Azo Dyes: Enhanced Adsorption Performance of Titanium Dioxide-Modified Kaolin Clay in Wastewater Treatment

Authors

Destiny Okoromi1

Affiliation: Department of Chemical Engineering, Faculty of Engineering, University of Benin, Edo State, Nigeria

Favour Ugbodu1

Affiliation: Department of Chemical Engineering, Faculty of Engineering, University of Benin, Edo State, Nigeria

Isaac Enuma2

Affiliation: Department of Civil Engineering, Faculty of Engineering, University of Benin, Edo State, Nigeria

Toheeb Animashaun3

Affiliation: Department of Civil Engineering, Obafemi Awolowo University, Ile-Ife, Nigeria

Owolabi Bankole4

Affiliation: Department of Chemical Sciences, Faculty of Science, Adekunle Ajasin University, Ondo State, Nigeria

Abraham Ajayi4

Affiliation: Department of Chemical Sciences, Faculty of Science, Adekunle Ajasin University, Ondo State, Nigeria

Confidence Anucha5

Affiliation: Department of Agricultural and Bio-Environmental Engineering, Federal Polytechnic Ede, Osun State, Nigeria

Alex Odia6

Affiliation: Department of Chemistry, University of Delta, Delta State, Nigeria

Princeton Otiasah7

Affiliation: Department of Chemical Engineering, Rivers State University, Rivers State, Nigeria

Abstract

This study aims to assess the effectiveness of both activated and inactivated clay in removing synthetic azo dyes from industrial wastewater. Due to their toxicity and persistence, dyes such as Congo Red, Sudan Black, Methyl Orange, and Methylene Blue pose serious environmental threats. Conventional treatment methods are often costly and unsustainable, making it necessary to explore more affordable and eco-friendly alternatives. This research investigates the adsorption potential of kaolin clay under different conditions, including variations in adsorbent dosage, contact time, pH, temperature, and initial dye concentration. Furthermore, the study examines adsorption kinetics and thermodynamic behavior to gain a deeper understanding of the mechanisms involved in dye removal.

To achieve this, the clay adsorbent was characterized using analytical techniques such as X-ray Diffraction (XRD), X-ray Fluorescence (XRF), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and Energy Dispersive X-ray Spectroscopy (EDX) to determine its structural, chemical, and physical properties. Batch adsorption experiments were conducted to evaluate dye removal efficiency. The adsorption process was analyzed using kinetic models, including pseudo-first-order, pseudo-second-order, and intra-particle diffusion models. Additionally, thermodynamic parameters such as enthalpy, entropy, and Gibbs free energy were assessed to determine the feasibility and spontaneity of adsorption. The effects of key factors such as adsorbent dosage (0.5g–2.5g), pH (2–11), contact time (30–75 minutes), temperature (30°C–70°C), and dye concentration (50–150 mg/L) were examined to optimize adsorption conditions.

The results demonstrate that both kaolin with titanium dioxide and plain kaolin effectively remove dyes, with activated clay exhibiting superior adsorption performance due to its increased surface area and porosity. The adsorption process follows pseudo-second-order kinetics, indicating that chemisorption is the primary mechanism. Isotherm studies suggest monolayer adsorption, with the Langmuir and Freundlich models providing insights into adsorption capacity and surface heterogeneity. Thermodynamic analysis confirms that adsorption is spontaneous and exothermic, with higher efficiency at lower temperatures. These findings highlight the potential of clay as an inexpensive and sustainable solution for treating dye-contaminated wastewater, offering a practical alternative to conventional treatment methods.

Keywords

Kaolin clay Titanium dioxide Adsorption Mixed azo dyes Wastewater treatment Pseudo-second-order kinetics Freundlich isotherm Chemisorption Sustainable remediation Dye removal

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How to Cite

APA Style:

Okoromi, D., Ugbodu, F., Enuma, I., Animashaun, T., Bankole, O., Ajayi, A., Anucha, C., Odia, A., & Otiasah, P. (2025). Sustainable Remediation of Synthetic Azo Dyes: Enhanced Adsorption Performance of Titanium Dioxide-Modified Kaolin Clay in Wastewater Treatment. International Journal of Advanced Research in Engineering and Related Sciences, 1(5), 45-62.

IEEE Style:

D. Okoromi, F. Ugbodu, I. Enuma, T. Animashaun, O. Bankole, A. Ajayi, C. Anucha, A. Odia, and P. Otiasah, "Sustainable Remediation of Synthetic Azo Dyes: Enhanced Adsorption Performance of Titanium Dioxide-Modified Kaolin Clay in Wastewater Treatment," International Journal of Advanced Research in Engineering and Related Sciences, vol. 1, no. 5, pp. 45-62, 2025.

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