Abstract

The presence of antibiotics in water discharges represents a hazard for the ecosystems, as it could affect the biota equilibrium at the micro and macroscales. Consequently, it is crucial to develop effective adsorption and oxidation technologies to remove antibiotics from water. Herein, we assessed the effectivity and stability of a metal organic framework-biomass hybrid (MIL-53(Al)@RH) for the removal of oxytetracycline (OTC) via adsorption and photocatalytic degradation. Under equilibrated conditions, the hybrid retained 165 mg g- 1 OTC. When adsorption and photocatalytic degradation were arranged in tandem, the system removed 99 % of OTC with a dose of 2.83 mg H2O2/mg OTC. The thermo-kinetic interpretation of the adsorption measurements was well described by Sips isotherm and pseudo-second kinetic models, which along with the heat of adsorption (-104.8 kJ mol- 1) suggest a chemical interaction between the OTC and MIL-53(Al)@Rice Husk hybrid active centres. The MIL-53(Al)@RH hybrid demonstrated a remarkable stability with an OTC removal above 90 % after 10 operational cycles. Moreover, pyrolysis of OTC-saturated hybrid led to a carbonaceous structure which demonstrated an outstanding OTC adsorption capacity (221 mg g- 1 OTC). The results demonstrate that the MIL53(Al)@RH hybrid presents a significant prospect for combined adsorption-photocatalytic treatment of water bodies contaminated with antibiotics.