AUTHOR=Jalloul Ghadeer , Al-Mousawi Assi , Chocr Farah , Merhi Alaa , Awala Hussein , Boyadjian Cassia 

TITLE=Fe-Sensitized Zeolite Supported TiO2 for the Degradation of Tetracycline Using Blue LED Irradiation

JOURNAL=Frontiers in Environmental Science

VOLUME=10

YEAR=2022

URL=https://www.frontiersin.org/journals/environmental-science/articles/10.3389/fenvs.2022.873257

DOI=10.3389/fenvs.2022.873257

ISSN=2296-665X

ABSTRACT=<p>In this study, we investigated the photocatalytic degradation as a potential treatment of tetracycline (TC) antibiotic contaminated water using TiO<sub>2</sub> semiconductor. To expand the activity of TiO<sub>2</sub> into the visible light region and to enhance its adsorption capacity for TC, we explored its modification <italic>via</italic> sensitization with Fe ions and <italic>via</italic> immobilization on beta (BEA) zeolite support. The nano-sized beta zeolite, synthesized using the seed-assisted procedure, was used to immobilize TiO<sub>2</sub> initially prepared by the sol-gel method. The immobilized TiO<sub>2</sub>/BEA catalyst was further ion exchanged with Fe<sup>3+</sup> ions using FeCl<sub>3</sub> precursor. Fe<sup>3+</sup> modified TiO<sub>2</sub>/BEA (Fe-TiO<sub>2</sub>/BEA) catalyst was characterized using SEM, XRD, BET, UV-VIS DRS, and FTIR. After the immobilization of TiO<sub>2</sub> over BEA, the surface area of TiO<sub>2</sub> increased from 90 to 530 m<sup>2</sup>/g and similarly its TC adsorption efficiency increased from 10% to 33%. The photocatalytic performance of the Fe-TiO<sub>2</sub>/BEA was evaluated under blue LED light for TC degradation. Fe-TiO<sub>2</sub>/BEA exhibited higher TC removal efficiency (100%) compared to TiO<sub>2</sub> (80%) after 90 min of irradiation using 50 W blue LED light for a 250 mg/L initial catalyst concentration and 20 mg/L TC concentration. The enhanced performance of the final catalyst was a result of the expanded surface area due to the immobilization of the TiO<sub>2</sub> on the BEA zeolite, which resulted in an improved TC adsorption. Moreover, the presence of Fe<sup>3+</sup> ions reduced the band gap energy of the TiO<sub>2,</sub> hence led to a red shift in its absorption spectrum to the visible light region and minimized the extent of the recombination of the charge carriers.</p>