Fe-doped zeolitic imidazolate framework-8 as superior adsorbent for enhanced ciprofloxacin removal from aqueous solution

It’s extremely urgent to remove ciprofloxacin (CIP) pollutant from wastewater since the extensively used CIP is difficult to be degraded in natural environment, seriously threating the ecological environment and human health. Herein, a series of Fe-doped zeolitic imidazolate framework-8 (Fe-ZIF-8) adsorbents were fabricated by doping Fe ion into the ZIF-8. Systematic adsorption experiments were conducted to evaluate the possibility of Fe-ZIF-8 in removing CIP from aqueous solutions. Accordingly, the maximum adsorption capacity of Fe-ZIF-8 for CIP could reach an ultrahigh value of 1484 mg g −1 , which is higher than that of any reported adsorbents. The CIP adsorption on Fe-ZIF-8 followed pseudo-second-order kinetics model and fitted well with Freundlich isotherm model, indicating the presence of the chemosorption and multilayer adsorption. The outstanding adsorption capacity of CIP could be ascribed to the high surface area and large pore volume of Fe-ZIF-8 as well as the synergetic effects including surface complexation, electrostatic attraction, π-π and hydrogen bonding interactions. These unrivalled traits certify the great potential of Fe-ZIF-8 in practical application.