Current research on the photocatalytic activity of TiO2 mainly focuses on its nano- or micro-particle forms, which are difficult to recycle and apply in real engineering applications. This study aims to apply a small pilot of TiO2 in the ceramic form to remove carbamazepine (CBZ) from an aqueous solution under simulated sunlight. A high removal efficiency up to >99% was shown in a 5 mg L−1 CBZ solution after 6 h of irradiation with a total energy of 150.92 kJ. The kinetic degradation was not affected in an alkaline solution (at pH 7, pH 10, and pH 13) but was faster under acidic conditions (pH 2) in which CBZ existed in the protonated form. The presence of NO3− (10–50 mg L−1) slightly affected the photodegradation of CBZ while humic acid significantly reduced the photocatalytic activity. In addition, the presence of major ions in water also had a negative effect at concentrations between 10 and 50 mg L−1. The MS/MS was used to identify the transformation products of CBZ, and a possible degradation mechanism was proposed. The toxicity of CBZ and the by-products was primarily evaluated. The results showed that TiO2 ceramics show high reusability and stability with a photocatalytic performance of >95% and a mass loss of <5% after 90 degradation cycles.

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The overuse of antibiotics is losing its effectiveness due to increased antibiotic resistance in bacteria. Over the last two decades, the evaluation of antibiotic residues in the environment has greatly attracted the attention of researchers around the world. The more new groups of antibiotics were validated to use in medical treatment, the more antibiotic residues were discharged into the environment. In this work, a combined SPE-UPLC-MS/MS method was developed and validated for simultaneously analyzing 9 antibiotic compounds belonging 3 different groups which are tetracyclines (tetracycline – TET, chlortetracycline – CHL, oxytetracycline – OXY), fluoroquinolones (ciprofloxacin – CIP, norfloxacin – NOR, ofloxacin – OFL) and macrolides (azithromycin – AZI, erythromycin – ERY, clarithromycin – CLA) in surface water. All target analytes were separated on a reversed-phase column (Water BEH C18 column, 1.7 µm particle size, 100 x 2.1 mm) coupled with a mass in tandem employing positive electrospray ionization (+ESI). All target analytes were well separated with an overall run time of 16 minutes. The limit of detection was from 0.2 to 10 µg L-1. The extraction process has been successfully optimized using the HLB column (Oasis, 6mL, 200mg, Waters) with recoveries from 71 to 125%. The optimized method was finally applied to analyze ten surface water samples (lake and river). OFL, CLA, and ERY were most found in lake samples at concentrations from 35 – 570.3 ng.L-1 while only CIP was found in all river samples. The other compounds were also detected in both types of samples but the concentrations were lower than the quantification limit.

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