Zr-based MOF gel prepared by ultrasonication for effective removal of antibiotic drug from aqueous environments

Abstract

Herein a Zr-based metal organic framework hydrogel (MOF-Zr; UiO-66) is synthesized. The prepared MOF is characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier-transform infrared (FTIR), Brunauer-Emmett-Teller (BET) surface area measurements and thermogravimetric analysis (TGA). The UiO-66 MOF is used effectively for the removal of an antibiotic; Ciprofloxacin, which is considered harmful when accumulated in water sources. The variation of operational factors that alter the drug removal are studied such as initial drug concentration, hydrogel (sorbent) used and the addition of some anions and cations. The study shows that the uptake efficiency of the MOF to the drug increases upon the addition of humic acid or sodium chloride to the solution matrix. A maximum uptake capacity of Ciprofloxacin onto the MOF reaches 333 mg g–1. Different isotherms (Langmuir, Freundlich, and Temkin) are applied to the adsorption process and their corresponding parameters are reported. The kinetic model follows a pseudo-second order mechanism. Conclusively, UiO-66 is a promising super adsorbent material for pharmaceutical pollutants from waters.