TiO2 is promising for photocatalytic treatment of water contaminated with organic micropollutants. However, it is hard to recover TiO2 slurry from water. Energy intensive separation methods are required to recover TiO2, which is a setback for effective usage of TiO2 for water treatment. Herein, we present nano-TiO2 immobilized with Polyvinylidene fluoride spongy beads (TP) by simple phase inversion of mixture of TiO2 (1 %), PVDF (13 %) and PVP (0.7 %), for degradation of Ciprofloxacin (CIP), a micropollutant in water under UVA LED irradiation with easy TP recovery. Stable immobilization of TiO2 with PVDF beads is attributed to interactions between Ti-F atoms. Pseudo first order rate constant value (kobs = 0.0761 min-1) was determined for degradation of CIP by TP. Radical scavenging, chronoamperometry and ESR analysis revealed the presence of O2-•, h+, HO• and 1O2 reactive species. LC-HRMS analysis detected ten degradation byproducts with plausible degradation pathways. Importantly, antibacterial activity of CIP against Bacillus subtilis and Escherichia coli was totally removed after 60 min treatment. TP beads were easily recovered by using a simple strainer. TP was recovered and reused 30 times, and no significant TiO2 leaching into water demonstrated its stable immobilization. TP photocatalysis under UVA LED irradiation proves an energy efficient treatment method with electrical energy per order of 24.20 kWh/m3/order. Overall, the study highlights a concrete way to effectively use TiO2 photocatalyst for water treatment by immobilization via a simple phase inversion method.
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