Seid, Mingizem Gashaw Son, Aseom Cho, Kangwoo Byun, Jeehye Hong, Seok Won 2024-01-19T10:04:15Z 2024-01-19T10:04:15Z 2023-02-23 2023-02 0043-1354 https://pubs.kist.re.kr/handle/201004/114040 Immobilized and visible-light-active titanium dioxide (TiO2) is widely used for water treatment. However, the accelerated generation of degradation byproducts is a potential risk of TiO2-based photocatalysis. This study aimed to investigate the structural effect of engineered TiO2 samples on the formation of major nitrosamines during photocatalysis. The nitrogen-containing impurities and leached metal ions from doped-TiO2 samples could exacerbate nitrosamine formation potential (FP) in distilled water, secondary effluent, and chloraminated water. Doped-TiO2 with 2-ethylimidazole, trimethylamine, triethylamine, and N-carbon nanotubes could leach in the range of 47-64 ng L-1 nitrosamines (including N-nitrosomethylethylamine, N-nitrosodiethylamine, N- nitrosodimethylamine, and N-nitrosopyrrolidine) even under dark conditions. Furthermore, we investigated the role of metal dopants on nitrosamine-FP during the chloramination of precursors such as dimethylamine and microcystin-LR. Metal ions such as Cu that leached from the metal-doped catalysts may catalyze the nitrosamine-FP. Therefore, pre-purification (washing) and immobilization of doped-TiO2 samples on substrates are suggested to remove a considerable amount of nitrosamines. However, during the prolonged tryout, the selection of sub-strates was critical. Polymeric supports, such as polyimide and polyvinylpyrrolidone, can produce up to 85 ng L-1 nitrosamine, whereas TiO2 immobilized onto steel mesh can remove nitrosamine formation during photo-catalytic oxidation followed by chloramination. This study systematically screened a diverse range of dopants, supports, and solvents in engineered TiO2 photocatalysts, in 61 samples, and provided novel insights into their effect on nitrosamine formation. English Elsevier BV Doped and immobilized titanium dioxide photocatalysts as a potential source of nitrosamine formation Article 10.1016/j.watres.2023.119573 1 Water Research, v.230 Water Research 230 Y scie scopus 000921532400001 2-s2.0-85145826403 Engineering, Environmental Environmental Sciences Water Resources Engineering Environmental Sciences & Ecology Water Resources Article BY-PRODUCT FORMATION N-NITROSODIMETHYLAMINE MICROCYSTIN-LR WATER CHLORAMINATION DEGRADATION MEMBRANES IMPACT MONOCHLORAMINE NANOPARTICLES Photocatalysis Doped titanium dioxide Nitrosamine Immobilization Chloramination