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

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 degrees 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 (R-2 = 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 (R-2 = 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.