Facile synthesis of Zn/Co LDH for the removal of oxytetracycline from wastewater: Experimental and DFT-Based analysis

• Published in: Chemical engineering science 2024-01, Vol.283, p.119399, Article 119399
• Main Authors: Mutahir, Sadaf, Akram, Shamaila, Asim Khan, Muhammad, Deng, Haishan, Naglah, Ahmed M., Almehizia, Abdulrahman A., Al-Omar, Mohamed A., Ibrahim Alrayes, Faris, Refat, Moamen S.
• Format: Article
• Language: English
• Subjects: Adsorption; Langmuir; Oxytetracycline; Theoretical studies; Zn/Co LDH
• ISSN: 0009-2509; 1873-4405
• DOI: 10.1016/j.ces.2023.119399

[Display omitted] •Synthesis of Zn/Co LDH to remove Oxytetracycline from Wastewater.•Zn/Co LDH showed 79 % removal of OTC.•The maximum adsorption capacity was achieved at pH 8.•Langmuir isotherm model best suits the removal of OTC.•Pseudo-second-order kinetic model best suits the removal of OTC.•The adsorption mechanism was based on hydrogen bonding (H.B), π-π interaction, ion exchange, and electrostatic interaction. Zn/Co layer double hydroxide (LDH) was first time synthesized for the removal of oxytetracycline (OTC) from aqueous solution. It was characterization by XRD, FTIR, BET, and SEM. The adsorption capacity of Zn/Co LDH for OTC was investigated by batch experimental method at different parameters and adsorption capacity was significantly enhanced to 387.59 mg.g−1 at pH = 8 and T = 15 °C. The kinetic and isothermal studies were performed at the best-selected pH and temperature with the help of different models. The adsorption kinetics plots were consistent with the pseudo-second-order model (R2 = 0.9935), indicating chemical adsorption through electrostatic interactions. The adsorption isotherm curves were more accorded with the Langmuir model as compared to the Freundlich model (R2 = 0.9986) indicating the monolayer mechanism of adsorption. The adsorption mechanism was well explained by DFT studies. The study suggests Zn/Co LDH has great potential for the removal of OTC at a large scale for wastewater treatment.