Adsorptive removal of carbamazepine and ibuprofen from aqueous solution using a defective Zr-based metal-organic framework

In order to protect human health, animals, and the environment, it is essential to eliminate pharmaceutical substances like carbamazepine (CBZ) and ibuprofen (IBU) from water. Herein, the adsorption of CBZ and IBU was investigated from water using a Zr-based metal-organic framework (MOF). UiO-67(Zr)s with a variety of defects, obtained by benzoic acid (BA) modulator, and commercial activated carbon were applied to the adsorptive removal of CBZ and IBU. One MOF, UiO-67(Zr)-BA(10), showed impressive maximum adsorption capacities for CBZ and IBU (294 and 213 mg/g, respectively). UiO-67(Zr)-BA(10) showed much higher adsorption of CBZ, compared with any MOF and MOF composites; the adsorption capacity of the MOF for CBZ is similar to 4.5 times that of commercial activated carbon. The efficient CBZ adsorption over UiO-67(Zr)-BA(10), under a wide range of pH conditions, might be attributed to the synergistic effects between porosity and defect sites; and explained with pi-pi, H-bonding, and van der Waals interactions. Additionally, the durability of the adsorbent allowed for simple regeneration even after several cycles without any noticeable loss in adsorptive performance. This work might provide a valuable insight, like loading adequate defects and increased porosity, in developing efficient MOF-based adsorbents for purification of water contaminated with pharmaceuticals.