Adsorption and photocatalytic removal from water of marbofloxacin (MAR) and enrofloxacin (ENR), two fluoroquinolone (FQ) antibiotics widely present in surface waters, were investigated on zeolite Y derivatized with three different TiO2 catalysts (P25 Degussa and TiO2 obtained by optimization of a sol–gel method). The prepared materials were characterized by X-rays powder diffraction (XRPD), scanning electron microscopy (SEM), BET analysis and diffuse reflectance spectroscopy (DRS). TiO2-derivatization improved the adsorption capacities of zeolite Y for FQs and promoted the sunlight-induced degradation of FQs adsorbed (solid-state photodegradation), not investigated in literature yet. A large FQs removal (3 mg g-1) occurred in about 2 h (residual adsorbed FQs < 0.03%). The degradation curves of FQs and the evolution profiles of the photoproducts were monitored, after microwave-assisted extraction, by highperformance liquid chromatography coupled to UV detection (HPLC-UV), thus proving the effectiveness of solar radiation in the photocatalytic removal of the drugs adsorbed on TiO2-modified zeolites, that can be recycled for further adsorption/photodegradation cycles, with no loss of sorption capability and photocatalytic activity. A complete removal of FQs from the outlet of a wastewater treatment plant samples, spiked with MAR and ENR at the micrograms per litre levels, was obtained with the best performing modified zeolite.
TiO2-modified zeolites for fluoroquinolones removal from wastewaters and reuse after solar light regeneration
MARASCHI, FEDERICA;STURINI, MICHELA;SPELTINI, ANDREA;PRETALI, LUCA;PROFUMO, ANTONELLA;
2014-01-01
Abstract
Adsorption and photocatalytic removal from water of marbofloxacin (MAR) and enrofloxacin (ENR), two fluoroquinolone (FQ) antibiotics widely present in surface waters, were investigated on zeolite Y derivatized with three different TiO2 catalysts (P25 Degussa and TiO2 obtained by optimization of a sol–gel method). The prepared materials were characterized by X-rays powder diffraction (XRPD), scanning electron microscopy (SEM), BET analysis and diffuse reflectance spectroscopy (DRS). TiO2-derivatization improved the adsorption capacities of zeolite Y for FQs and promoted the sunlight-induced degradation of FQs adsorbed (solid-state photodegradation), not investigated in literature yet. A large FQs removal (3 mg g-1) occurred in about 2 h (residual adsorbed FQs < 0.03%). The degradation curves of FQs and the evolution profiles of the photoproducts were monitored, after microwave-assisted extraction, by highperformance liquid chromatography coupled to UV detection (HPLC-UV), thus proving the effectiveness of solar radiation in the photocatalytic removal of the drugs adsorbed on TiO2-modified zeolites, that can be recycled for further adsorption/photodegradation cycles, with no loss of sorption capability and photocatalytic activity. A complete removal of FQs from the outlet of a wastewater treatment plant samples, spiked with MAR and ENR at the micrograms per litre levels, was obtained with the best performing modified zeolite.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
