Metal Oxide-Impregnated Biochar for Azo Dye Remediation as Revealed through Kinetics, Thermodynamics, and Response Surface Methodology

Adeel Aslam; Fozia Batool; Sobia Noreen; Ehab A Abdelrahman; Muhammad Mustaqeem; Bedur Faleh A Albalawi; Allah Ditta

doi:10.1021/acsomega.3c05321

Metal Oxide-Impregnated Biochar for Azo Dye Remediation as Revealed through Kinetics, Thermodynamics, and Response Surface Methodology

ACS Omega. 2024 Jan 17;9(4):4300-4316. doi: 10.1021/acsomega.3c05321. eCollection 2024 Jan 30.

Authors

Adeel Aslam¹, Fozia Batool¹, Sobia Noreen¹, Ehab A Abdelrahman^{2

3}, Muhammad Mustaqeem¹, Bedur Faleh A Albalawi⁴, Allah Ditta^{5

6}

Affiliations

¹ Institute of Chemistry, University of Sargodha, Sargodha 40100, Pakistan.
² Department of Chemistry, College of Science, Imam Mohammad Ibn Saud Islamic University (IMSIU), Riyadh 11623, Saudi Arabia.
³ Chemistry Department, Faculty of Science, Benha University, Benha 13518, Egypt.
⁴ Department of Biology, University of Tabuk, Tabuk 47512, Saudi Arabia.
⁵ Department of Environmental Sciences, Shaheed Benazir Bhutto University Sheringal, Upper Dir 18000, Pakistan.
⁶ School of Biological Sciences, The University of Western Australia, 35 Stirling Highway, Perth, WA 6009, Australia.

Abstract

This study reports for the first time the adsorption capacity of a novel adsorbent Croton bonplandianus Baill. biochar. Its adsorption capacity was further enhanced by loading magnetic composites on it, which makes it an efficient medium for the adsorption of dyes. Two azo dyes, Basic Brown 1 (BB₁) and Basic Orange 2 (BO₂), were studied for their effective adsorption from aqueous media. A comprehensive characterization was performed by using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) to study the properties of Fe₂O₃-loaded C. bonplandianus Baill. biochar (FO-CBPBB). A series of batch experiments were conducted to optimize various parameters (pH, contact time, adsorbent amount, initial BB₁ and BO₂ concentrations, and temperature) for the maximum adsorption of BB₁ and BO₂ on the FO-CBPBB adsorbent. The percentage of BB₁ and BO₂ dyes that adsorb to FO-CBPBB under the best experimental circumstances (pH of solution 7, contact time 80 min, temperature of solution 40 °C, initial BB₁ and BO₂ dye concentrations 80 mg L^-1, and adsorbent dose 1 g L^-1) was 93 and 95%, respectively. The best adsorption of BB₁ and BO₂ was accomplished by optimizing the effects of several factors, including the starting dye concentration, contact time, and temperature, based on the central composite design. The Freundlich and Langmuir isotherm models were used to examine the equilibrium data. The Langmuir isotherm with the greatest adsorption capacity and R² value effectively captured the experimental results. When kinetic parameters were investigated, it was found that pseudo-second-order was appropriate, reflecting the fact that the dye-adsorbent interaction was the rate-controlling factor in this study. The sorption process was endothermic and spontaneous, as shown by the thermodynamic variables. Based on the interaction between the adsorbent and azo dyes, it was concluded that the adsorption process was electrostatic in nature. Adsorbents that have been synthesized can effectively remove azo dyes from wastewater. Excellent regeneration efficiency was exhibited by FO-CBPBB, which makes it an eco-friendly and cost-effective alternative to other costly techniques applied for water purification.