Development of MOF-MXene composite for the removal of dyes and antibiotic

Abstract

Metal-organic framework composites have gained great attention in the adsorptive remediation of environmental pollutants because of their unique features such as tunable pore size and modification of their framework. The main objective of this study was to fabricate UiO-66/MXene (Ti3AlC2) composite through solvothermal method and newly synthesized adsorbent was characterized by utilizing powder X-Ray diffraction analysis, Fourier transform infrared spectroscopy, and scanning electron microscopy. Exceptional adsorption properties of UiO-66/MXene composite were verified by adsorption of two model dyes i.e., methylene blue (MB), rhodamine B (RhB), and antibiotic i.e., tetracycline (OTC). Adsorption process was studied by applying different optimization parameters such as pH, contact time, adsorbent dose, and initial concentration of MB, RhB, and OTC. Results showed that UiO-66/MXene composite have best adsorption performance with removal rate of 98 % for MB, 97 % for RhB, and 99 % for OTC. Four kinetic models e.g., pseudo-first order, pseudo-second order, intraparticle diffusion and Elovich models were applied, and results showed that kinetic process was well described by pseudo-second-order kinetic model for dyes and antibiotic. Maximum adsorption capacity (qm) of UiO-66/MXene composite was achieved up to 312, 285, and 476 mg/g for MB, RhB, and OTC respectively. Four different isotherm models are used such as Langmuir, Freundlich, Dubinin–Kaganer–Radushkevich (DKR), and Temkin, the study shows that the Langmuir isotherm model describes well for the adsorption of MB, RhB, and OTC. Thermodynamic studies suggested that the process of adsorption was spontaneous and endothermic for dyes and antibiotic. The results recommend that the successful synthesis of UiO-66/MXene composite offers beneficial visions in the development of MOF composites as adsorbents for water refining.