Binary metal organic frameworks (UIO-66 and ZIF-67) for adsorptive removal of Sb

ZIF-67 contains large amounts of micropores and nitrogen that act as active centers. In addition, due to Zr-bound hydroxides exist in the metal clusters of UIO-66, Zr-O-Sb complexes by surface complexation is anticipated to occur. To tap the potential of UIO-66 and ZIF-67, we synthesized binary metal organic frameworks with UIO-66 and ZIF-67 (UIO-66/ZIF-67x, x represents the Zr/Co atomic ratio) and employed for the adsorption removal of Sb(III) from aqueous solutions. The obtained samples were characterized by X-ray diffraction (XRD), N2 adsorption/desorption isotherms, scanning electron microscope (SEM), and transmission electron microcopy (TEM). The binary MOFs with a Zr/Co atomic ratio of 0.45 have the best adsorption performance with the maximum adsorption capacity of 302.4 ± 6.4 mg/g towards Sb(III), which was much higher than the majority of existing antimony adsorbents. It also exhibits much higher than the majority of existing antimony adsorbents. Besides, it shows good performance in adsorbing Sb(III) from textile wastewater and the concentration of Sb(III) decreased from 0.845 to 0.413 mg/L. Meanwhile, about 67.5% phosphorus and 19.1% chemical oxygen demand (COD) removal were achieved within 5 h. This study indicates that the binary UIO-66 and ZIF-67 MOFs has significant potential in the adsorption removal of Sb(III) from aqueous solutions.