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Graphical abstract Highlights • A PVDF membrane with immobilized TiO 2 was prepared and employed for photocatalysis. • A mixture of pharmaceuticals in secondary wastewater effluent was treated. • Configuration with supported catalyst gave lowest electrical energy consumption. Abstract A promising membrane configuration based on immobilized TiO 2 on poly(vinylidene fluoride) (PVDF) dual layer hollow fibre membranes was prepared and successfully employed for the photocatalytic degradation of eight pharmaceuticals. Experiments were carried out in a flow reactor of 0.5 L equipped with a lamp emitting at 254 nm, treating groundwater and secondary wastewater effluent. The efficiency of the new catalyst to phototransform target micropollutants was demonstrated, being dependent on the selected compound. Only the application of photocatalysis using the supported catalyst allowed to increase the phototransformation rate of trimethoprim, metoprolol and carbamazepine treating secondary wastewater effluent (1.4–2.2 times faster than photolysis). The determination of electrical energy per order of magnitude of transformation (EEO) confirmed the lowest energy requirements to transform selected pharmaceuticals in secondary effluent employing the supported catalyst (33–58 kW h m−3 compared to 49–79 kW h m−3 applying only photolysis). The detection and identification of transformation products formed during the investigated treatments was performed by UPLC-QTOF/MS/MS. 156 transformation products were detected showing two different types of time profiles, namely a bell-shape trend or a constant increase along reaction time thus accumulating in the reaction mixture. The chemical structure for 19 out of 156 detected compounds was proposed as derived from parent compounds spiked in the secondary effluent. [ABSTRACT FROM AUTHOR]

The photocatalytic efficiency of an innovative UV-light catalyst consisting of a mesoporous TiO2 coating on glass fibers was investigated for the degradation of pharmaceuticals (PhACs) in wastewater effluents. Photocatalytic activity of the synthesized material was tested, for the first time, on a secondary wastewater effluent spiked with nine PhACs and the results were compared with the photolysis used as a benchmark treatment. Replicate experiments were performed in a flow reactor equipped with a UV radiation source emitting at 254 nm. Interestingly, the novel photocatalyst led to the increase of the degradation of carbamazepine and trimethoprim (about 2.2 times faster than the photolysis). Several transformation products (TPs) resulting from both the spiked PhACs and the compounds naturally occurring in the secondary wastewater effluent were identified through UPLC-QTOF/MS/MS. Some of them, produced mainly from carbamazepine and trimethoprim, were still present at the end of the photolytic treatment, while they were completely or partially removed by the photocatalytic treatment. [ABSTRACT FROM AUTHOR]

Carbamazepine (CBZ) is a pharmaceutical compound recalcitrant to conventional wastewater treatment plants and widely detected in wastewater bodies. In the present study, advanced oxidation processes for carbamazepine removal are investigated, with particular regard to the degradation pathways of carbamazepine by photoelectrocatalysis and conventional photocatalysis. Photoelectrocatalysis was carried out onto TiO2 meshes obtained by Plasma Electrolytic Oxidation, a well-known technique in the field of industrial surface treatments, in view of an easy scale-up of the process. By photoelectrocatalysis, 99% of carbamazepine was removed in 55 min while only 65% removal was achieved by photolysis. The investigation of the transformation products (TPs) was carried out by means of UPLC-QTOF/MS/MS. Several new TPs were identified and accordingly reaction pathways were proposed. Above 80 min the transformation products disappear, probably forming organic acids of low-molecular weight as final degradation products. The results demonstrated that photoelectrocatalysis onto TiO2 meshes obtained by plasma electrolytic oxidation is a useful alternative to common advanced oxidation processes as wastewater tertiary treatment aimed at removing compounds of emerging concern. [ABSTRACT FROM AUTHOR]