Assessment of 265-nm UV-LED for direct photolysis and advanced oxidation of N-nitrosamines and 1,4-dioxane

Fujioka, Takahiro; Kodamatani, Hitoshi; Yoshikawa, Takumi; Inoue, Daisuke; Ikehata, Keisuke

doi:10.1016/j.eti.2020.101147

Cited by 12 publications

(4 citation statements)

References 36 publications

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“…An integrating sphere and spectral radiometer (Labsphere, North Sutton, NH) were used to measure and confirm the optical power of the LEDs. The advantages of using LEDs instead of mercury lamps have been discussed elsewhere (Crystal, 2013; Fujioka et al, 2020; Ibrahim, 2012; Jo & Tayade, 2014).…”

Section: Methodsmentioning

confidence: 99%

2,4‐dinitroanisole transformation during advanced oxidation with ultraviolet light emitting diodes and hydrogen peroxide

Burdsall

Schober

Stubbs

et al. 2022

Water & Environment J

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This study investigated the kinetics and reaction mechanisms associated with advanced oxidation of 2,4-dinitroanisole (DNAN) with light emitting diodes (LEDs) in the UV/H 2 O 2 process. The pseudo first-order reaction rate constants for DNAN oxidation depended on the H 2 O 2 /DNAN molar ratio and were between 0.017 and 0.026 min À1 .Hydroxyl radical scavenging was strongly implicated by the experimental results. High mass spectrophotometric chromatograms showed the presence of several by-products, including three with ecotoxicity that is greater than that of DNAN. Transformation pathways were analysed using Density Functional Theory (DFT), which helped to predict the presence of experimentally detected DNAN by-products by considering Mulliken charges. This study is the first to elucidate DNAN transformation mechanisms using both experimental studies and computational chemistry.

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Section: Methodsmentioning

confidence: 99%

2,4‐dinitroanisole transformation during advanced oxidation with ultraviolet light emitting diodes and hydrogen peroxide

Burdsall

Schober

Stubbs

et al. 2022

Water & Environment J

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“…Novel photoreactors using UV LEDs had been developed for degradation of phenol, 30 drinking-water purification, 31 dye degradation [32][33][34] and removal of micropollutants such as antibiotics, pesticides or drugs of abuse. [35][36][37] Other applications have been in enhancing the removal of metals such as chromium 38 and the inactivation of different bacteria and parasites [39][40][41] or even coronavirus. 42 At present, numerous studies are investigating the development of new semiconductor materials that increase the efficiency of these devices, [43][44][45][46][47][48] portending a very promising future for this technology.…”

Section: Uv Ledmentioning

confidence: 99%

Chapter 4. Modelling Photochemical Processes for Water Disinfection

Casado¹,

García-Gil²,

Martín-Sómer³

et al. 2022

Chemistry in the Environment

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“…UV-LEDs are physically small, mercury-free, and characterized by fast startup time and long lifespan compared to the traditional mercury vapor lamps [17]. LEDs also emit light at specific wavelengths, allowing for flexible tailoring of UV system designs that combine selected wavelengths to achieve optimal inactivation of various pathogens [18], and mineralization and degradation of persistent contaminants [19][20][21][22]. Being a new technology, UV-LEDs suffer from low power and energy efficiencies at the shorter wavelengths; however, these parameters are constantly being improved [23].…”

Section: Introductionmentioning

confidence: 99%

UV-LED Combined with Small Bioreactor Platform (SBP) for Degradation of 17α-Ethynylestradiol (EE2) at Very Short Hydraulic Retention Time

et al. 2021

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Degradation of 17α-ethynylestradiol (EE2) and estrogenicity were examined in a novel oxidative bioreactor (OBR) that combines small bioreactor platform (SBP) capsules and UV-LED (ultraviolet light emission diode) simultaneously, using enriched water and secondary effluent. Preliminary experiments examined three UV-LED wavelengths—267, 279, and 286 nm, with (indirect photolysis) and without (direct photolysis) H2O2. The major degradation wavelength for both direct and indirect photolysis was 279 nm, while the major removal gap for direct vs. indirect degradation was at 267 nm. Reduction of EE2 was observed together with reduction of estrogenicity and mineralization, indicating that the EE2 degradation products are not estrogens. Furthermore, slight mineralization occurred with direct photolysis and more significant mineralization with the indirect process. The physical–biological OBR process showed major improvement over other processes studied here, at a very short hydraulic retention time. The OBR can feasibly replace the advanced oxidation process of UV-LED radiation with catalyst in secondary sedimentation tanks with respect to reduction ratio, and with no residual H2O2. Further research into this OBR system is warranted, not only for EE2 degradation, but also to determine its capabilities for degrading mixtures of pharmaceuticals and pesticides, both of which have a significant impact on the environment and public health.

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Assessment of 265-nm UV-LED for direct photolysis and advanced oxidation of N-nitrosamines and 1,4-dioxane

Cited by 12 publications

References 36 publications

2,4‐dinitroanisole transformation during advanced oxidation with ultraviolet light emitting diodes and hydrogen peroxide

2,4‐dinitroanisole transformation during advanced oxidation with ultraviolet light emitting diodes and hydrogen peroxide

Chapter 4. Modelling Photochemical Processes for Water Disinfection

UV-LED Combined with Small Bioreactor Platform (SBP) for Degradation of 17α-Ethynylestradiol (EE2) at Very Short Hydraulic Retention Time

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