Ceramized Fabrics and Their Integration in a Semi-Pilot Plant for the Photodegradation of Water Pollutants

The use of nano-photocatalysts for the water/wastewater purifications, particularly in developing regions, offers promising advantages over conventional technologies. TiO2-based photocatalysts deposited on fabrics represent an efficient solution for obtaining heterogeneous photocatalysts, which are easily adaptable in the already installed water treatment plants or air purification systems. Despite the huge effort spent to develop and characterize novel nano-photocatalysts, which are especially active under solar light, knowledge gaps still persist for their full-scale application, starting from the reactor design and scale-up and the evaluation of the photocatalytic efficiency in pre-pilot scenarios. In this study, we offered easily scalable solutions for adapting TiO2-based photocatalysts, which are deposited on different kinds of fabrics and implemented in a 6 L semi-pilot plant, using the photodegradation of Rhodamine B (RhB) as a model of water pollution. We took advantage of a multi-variable optimization approach to identify the best design options in terms of photodegradation efficiency and turnover frequency (TOF). Surprisingly, in the condition of use, the irradiation with a light-emitting diode (LED) visible lamp appeared as a valid alternative to the use of UV LED. The identification of the best design options in the semi-pilot plant allowed scaling up the technology in a 100 L pilot plant suitable for the treatment of industrial wastewater.

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Design of a Secondary Freeform Lens of UV LED Mosquito-Trapping Lamp for Enhancing Trapping Efficiency

Crystals ◽

10.3390/cryst8090335 ◽

2018 ◽

Vol 8 (9) ◽

pp. 335 ◽

Cited By ~ 3

Author(s):

Wei-Hsiung Tseng ◽

Diana Juan ◽

Wei-Cheng Hsiao ◽

Cheng-Han Chan ◽

Hsin-Yi Ma ◽

...

Keyword(s):

Light Intensity ◽

Intensity Distribution ◽

Light Emitting Diode ◽

Trapping Efficiency ◽

Axially Symmetric ◽

Light Intensity Distribution ◽

Light Emitting ◽

Led Light ◽

Uv Led ◽

Freeform Lens

In this study, our proposed ultraviolet light-emitting diode (UV LED) mosquito-trapping lamp is designed to control diseases brought by insects such as mosquitoes. In order to enable the device to efficiently catch mosquitoes in a wider area, a secondary freeform lens (SFL) is designed for UV LED. The lens is mounted on a 3 W UV LED light bar as a mosquito-trapping lamp of the new UV LED light bar module to achieve axially symmetric light intensity distribution. The special SFL is used to enhance the trapping capabilities of the mosquito-trapping lamp. The results show that when the secondary freeform surface lens is applied to the experimental outdoor UV LED mosquito-trapping lamp, the trapping range can be expanded to 100π·m2 and the captured mosquitoes increased by about 300%.

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Miniaturized UV-LED Array Chip Photochemical Vapor Generator Coupled with Point Discharge Optical Emission Spectrometer for Determination of Trace Selenium

Journal of Analytical Atomic Spectrometry ◽

10.1039/d1ja00290b ◽

2021 ◽

Author(s):

Mengtian Li ◽

Yi Luo ◽

Zhirong Zou ◽

Fujian Xu ◽

Xiaoming Jiang ◽

...

Keyword(s):

Light Emitting Diode ◽

Optical Emission ◽

Nano Tio2 ◽

Light Emitting ◽

Uv Led ◽

Led Array ◽

Point Discharge ◽

Photochemical Vapor Generation ◽

Optical Emission Spectrometer

An ultraviolet light emitting diode (UV-LED) array chip as irradiation source for nano-TiO2 catalyzed photochemical vapor generation (PCVG) was combined with a hollow electrode point discharge microplasma optical emission spectrometer...

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Computational modeling of ultraviolet light-emitting diode (UV-LED) reactor for water treatment

Water Research ◽

10.1016/j.watres.2019.115022 ◽

2019 ◽

Vol 166 ◽

pp. 115022 ◽

Cited By ~ 4

Author(s):

Majid Keshavarzfathy ◽

Fariborz Taghipour

Keyword(s):

Water Treatment ◽

Computational Modeling ◽

Ultraviolet Light ◽

Light Emitting Diode ◽

Light Emitting ◽

Uv Led

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Ultraviolet light-emitting diode (UV LED) trap the West Indian sweet potato weevil, Euscepes postfasciatus (Coleoptera: Curculionidae)

Applied Entomology and Zoology ◽

10.1007/s13355-012-0113-y ◽

2012 ◽

Vol 47 (3) ◽

pp. 285-290 ◽

Cited By ~ 16

Author(s):

Masako Katsuki ◽

Yusuke Omae ◽

Kensuke Okada ◽

Toru Kamura ◽

Takashi Matsuyama ◽

...

Keyword(s):

Sweet Potato ◽

Ultraviolet Light ◽

Light Emitting Diode ◽

West Indian ◽

The West ◽

Light Emitting ◽

Uv Led ◽

Sweet Potato Weevil ◽

Euscepes Postfasciatus

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3D Microlithography Using an Integrated System of 5-mm UV-LEDs with a Tilt-Rotational Sample Holder

Micromachines ◽

10.3390/mi11020157 ◽

2020 ◽

Vol 11 (2) ◽

pp. 157 ◽

Cited By ~ 2

Author(s):

Sabera Fahmida Shiba ◽

Hyeongmin Jeon ◽

Jong-Soo Kim ◽

Jong-Eun Kim ◽

Jungkwun Kim

Keyword(s):

Light Source ◽

Light Emitting Diode ◽

Vertical Direction ◽

Ultra Violet ◽

Integrated System ◽

Sample Holder ◽

Large Area ◽

Light Emitting ◽

Uv Led ◽

Uv Leds

This paper demonstrates a 3D microlithography system where an array of 5 mm Ultra Violet-Light Emitting Diode (UV-LED) acts as a light source. The unit of the light source is a UV-LED, which comes with a length of about 8.9 mm and a diameter of 5 mm. The whole light source comprises 20 × 20 matrix of such 5 mm UV-LEDs giving a total number of 400 LEDs which makes it a very favorable source with a large area for having a batch production of the desired microstructures. This light source is able to give a level of precision in microfabrication which cannot be obtained using commercial 3D printers. The whole light source performs continuous rotational movement once it is turned on. This can also move up and down in a vertical direction. This multidirectional light source also comprises a multidirectional sample holder. The light source teaming up with the multidirectional sample holder highly facilitates the process of fabrication of a huge range of 3D structures. This article also describes the different levels of characterization of the system and demonstrates several fabricated 3D microstructures including high aspect ratio vertical micro towers, twisted turbine structures, triangles, inclined pillar ‘V’ structures, and hollow horn structures as well.

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Optimization and scale-up of an LED-illuminated microalgal photobioreactor for wastewater treatment

Water Science & Technology ◽

10.2166/wst.2020.058 ◽

2019 ◽

Vol 80 (12) ◽

pp. 2352-2361

Author(s):

L. M. L. Silva ◽

A. F. Santiago ◽

G. A. Silva ◽

A. L. P. Castro ◽

L. S. Bastos ◽

...

Keyword(s):

Organic Matter ◽

Wastewater Treatment ◽

Wastewater Treatment Plants ◽

Light Emitting Diode ◽

Scale Up ◽

Operating Time ◽

Luminous Flux ◽

Light Emitting ◽

Operational Conditions ◽

Nitrogen Phosphorus

Abstract The use of light-emitting diode (LED)-illuminated photobioreactors with microalgae has been extensively studied for wastewater treatment. Most studies have used isolated microalgae species; however, this practice does not match the reality of conditions in wastewater treatment plants. Operational conditions that promote greater growth of algal biomass and that remove pollutants most effectively are disputed in the literature. In this context, LED-illuminated photobioreactors with microalgae were evaluated using multivariate analysis in order to optimize removal of pollutants (nitrogen, phosphorus, and carbonaceous organic matter). Three variables were evaluated: operating time, LED wavelength, and luminous flux intensity. A microalgae consortium was used in the photobioreactor. In addition to the LED-illuminated photobioreactors, control photobioreactors illuminated by sunlight were also operated. Using the results obtained in the optimization, a scaled-up reactor approximately 8.5 times larger in volume was operated to evaluate if the behavior would be maintained. The best operational conditions for the removal of pollutants were observed in LED-illuminated photobioreactors operated under a light intensity of 700 μmol·m−2s−1 for 15 days. Under these conditions, it was possible to remove 89.97% of carbonaceous organic matter, 86.50% of nitrogen, and 30.64% of phosphorus. The scaled-up photobioreactor operated with similar performance.

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Fabrication and antimicrobial effects of silver nanoparticle-poly(N-isopropylacrylamide)-poly(ferrocenylsilane) hydrogel composites

MRS Proceedings ◽

10.1557/opl.2012.1293 ◽

2012 ◽

Vol 1453 ◽

Author(s):

Xiaofeng Sui ◽

Xueling Feng ◽

Andrea Di Luca ◽

Clemens A. van Blitterswijk ◽

Lorenzo Moroni ◽

...

Keyword(s):

Light Emitting Diode ◽

Light Emitting ◽

Uv Led ◽

Hydrogel Network ◽

Redox Responsive ◽

Equilibrium Swelling ◽

Hydrogel Composites ◽

Equilibrium Swelling Ratio ◽

Strong Antimicrobial Activity

ABSTRACTNovel hydrogels composed of thermo-responsive poly(N-isopropylacrylamide) (PNIPAM) and redox-responsive poly(ferrocenylsilane) (PFS) macromolecules were formed by photopolymerization. PFS chains bearing acrylate side groups were copolymerized with NIPAM and N,N’-methylenebisacrylamide in tetrahydrofuran in a predetermined ratio under ultraviolet light-emitting diode (UV-LED) irradiation at a wavelength of 365 nm, in the presence of a photoinitiator. Crosslinking occurred smoothly, providing homogeneous hydrogels. The equilibrium swelling ratio, rheology and morphology of these hybrid PNIPAM-PFS-based hydrogels were investigated. In-situ fabrication of silver nanoparticles inside the hydrogel network via reduction of silver nitrate by the PFS chains led to hydrogel composites. These composites showed strong antimicrobial activity while maintaining a high biocompatibility with cells.

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