Field Performance Test of an Air-Cleaner with  Photocatalysis-Plasma Synergistic Reactors for  Practical and Long-Term Use

Ochiai, Tsuyoshi; Ichihashi, Erina; Nishida, Naoki; Machida, Tadashi; Uchida, Yoshitsugu; Hayashi, Yûji; Morito, Yuko; Fujishima, Akira

doi:10.3390/molecules191117424

Cited by 11 publications

(9 citation statements)

References 21 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Regarding the performance of the improved photocatalytic air cleaner, the performance of photocatalytic air cleaners have been reported but, for example, the decomposing ability test of acetaldehyde were different. (Yu et al, 2006;Sekine et al, 2011;Ochiai et al, 2014;Del Curto et al, 2016;Costarramone et al, 2017) Although it is difficult to compare the performance among photocatalytic air cleaners in the market, our photocatalytic air cleaner completely decomposed the acetaldehyde in the flow and closed air systems, indicating the excellent performance among photocatalytic air cleaners. …”

Section: Discussionmentioning

confidence: 80%

“…By reducing air pollution levels, countries can reduce the disease burden resulting from stroke, heart disease, lung cancer, and both chronic and acute respiratory diseases, including asthma (WHO, 2016a), as well as the burden caused by VOCs, particulate matter, and pathogens present in the environment that affect the health of humans. Photocatalysis appears to be one of the means of eliminating these risk factors and has been reported to decompose organic chemicals by reactive oxygen species generated by photocatalysis with titanium dioxide (TiO 2 ) and light (Fujishima and Honda, 1972;Ochiai et al, 2014). We previously developed a highly efficient photocatalytic air cleaner and characterized its efficacy in the decomposition of aldehyde and the inactivation of influenza virus infectivity.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Improved Photocatalytic Air Cleaner with Decomposition of Aldehyde and Aerosol-Associated Influenza Virus Infectivity in Indoor Air

Shiraki

Yamada

Yoshida

et al. 2017

Aerosol Air Qual. Res.

View full text Add to dashboard Cite

Air pollution caused by fine particulate matter (PM 2.5 ), volatile organic compounds, and bioaerosols is a major environmental risk to health. We developed a photocatalytic air cleaner for reducing the pollution levels of indoor air; we improved the photocatalytic system by using UV-LED for the removal of acetaldehyde and PM 2.5 and by reducing the weight and size of the system. The efficiency of photocatalysis depends on the surface area and materials. Therefore, we prepared a nanosized titanium dioxide (TiO 2 )-coated aluminum plate irradiated by UV-LED lamps (wavelength: 375 nm) as a photocatalytic air cleaner. Passing air continuously through a TiO 2 -coated aluminum plate (5 × 10 × 1 cm) under black light for 200 min decomposed 90% of 5 ppm acetaldehyde (12.4 µmol h -1 ) and generated two carbon dioxide molecules (25.43 µmol h -1 ) at a molar ratio of 1:2, indicating complete decomposition of acetaldehyde with high efficiency. This photocatalytic air cleaner was applied to the decomposition of acetaldehyde and inactivation and removal of aerosolassociated influenza virus. Acetaldehyde (20 ppm) in a 1-m 3 cubic space was eliminated in 60 min at a half-life of 8 min. The aerosol-associated infectivity and the RNA genome of influenza virus A/PR/8/1934 (H1N1) produced by a nebulizer in a 779-L cubic space were eliminated within 7 min; however, they were detectable for up to 28 minutes when the functional photocatalytic air cleaner was not used. The presence of intermediate breakdown products of influenza virus indicated that the virus was broken down by photocatalysis. Thus, the photocatalytic air cleaner efficiently decomposed and eliminated organic chemicals, acetaldehyde, and aerosol-associated influenza virus infectivity and viral RNA, indicating that it can clean and detoxify the indoor air in a closed space for maintaining a safer environment.

show abstract

Section: Discussionmentioning

confidence: 80%

Section: Introductionmentioning

confidence: 99%

Improved Photocatalytic Air Cleaner with Decomposition of Aldehyde and Aerosol-Associated Influenza Virus Infectivity in Indoor Air

Shiraki

Yamada

Yoshida

et al. 2017

Aerosol Air Qual. Res.

View full text Add to dashboard Cite

show abstract

“…Sul f ur balance(%) = c SO 2 + c SO 3 c in − c out × 100% (16) where c in and c out are the H 2 S concentration at the inlet and outlet of the reactor, respectively, while c SO 2 and c SO 3 are the outlet SO 2 and SO 3 concentrations.…”

Section: Experimental Set-upmentioning

confidence: 99%

“…In the last three decades, the combination of non-thermal plasma and heterogeneous catalysis, known as "plasma-catalysis" has been demonstrated as a promising emerging process for the removal of low concentration gas pollutants including odors with reduced formation of by-products and enhanced process performance [14][15][16][17]. Although LaMnO 3 perovskite type catalysts have been used in thermal catalytic reactions due to their relatively low cost, comparable activity, and thermal stability [18][19][20], the use of these catalysts in plasma chemical reactions for environmental clean-up or the synthesis of fuels and chemicals has been very limited.…”

Section: Introductionmentioning

confidence: 99%

Plasma Oxidation of H2S over Non-stoichiometric LaxMnO3 Perovskite Catalysts in a Dielectric Barrier Discharge Reactor

et al. 2018

View full text Add to dashboard Cite

In this work, plasma-catalytic removal of H2S over LaxMnO3 (x = 0.90, 0.95, 1, 1.05 and 1.10) has been studied in a coaxial dielectric barrier discharge (DBD) reactor. The non-stoichiometric effect of the LaxMnO3 catalysts on the removal of H2S and sulfur balance in the plasma-catalytic process has been investigated as a function of specific energy density (SED). The integration of the plasma with the LaxMnO3 catalysts significantly enhanced the reaction performance compared to the process using plasma alone. The highest H2S removal of 96.4% and sulfur balance of 90.5% were achieved over the La0.90MnO3 catalyst, while the major products included SO2 and SO3. The missing sulfur could be ascribed to the sulfur deposited on the catalyst surfaces. The non-stoichiometric LaxMnO3 catalyst exhibited larger specific surface areas and smaller crystallite sizes compared to the LaMnO3 catalyst. The non-stoichiometric effect changed their redox properties as the decreased La/Mn ratio favored the transformation of Mn3+ to Mn4+, which contributed to the generation of oxygen vacancies on the catalyst surfaces. The XPS and H2-TPR results confirmed that the Mn-rich catalysts showed the higher relative concentration of surface adsorbed oxygen (Oads) and lower reduction temperature compared to LaMnO3 catalyst. The reaction performance of the plasma-catalytic oxidation of H2S is closely related to the relative concentration of Oads formed on the catalyst surfaces and the reducibility of the catalysts.

show abstract

“…The aim of the research was to give polypropylene fibers the properties of accelerated photocatalytic decomposition of nicotine by modifying the fiber surface, using titanium dioxide doped with nanoparticles of silver (TiO 2 /Ag) as the decomposition activator. Titanium dioxide, particularly due to the dynamic development of nanotechnology, is now used in many processes of photocatalytic decomposition of organic substances (Fujishima et al 2008;Ochiai et al 2010Ochiai et al , 2014. It is applied, inter alia, onto textile materials in order to induce self-cleaning properties (Zhang et al 2012;Cieślak et al 2015;Bozzi et al 2005;Dastjerdi and Mojtahedi 2013;Tung and Daoud 2011;Radetic 2013;Cieślak et al 2009;Bourgeois et al 2012).…”

Section: Introductionmentioning

confidence: 99%

Removal of nicotine from indoor air using titania-modified polypropylene fibers: nicotine decomposition by titania-modified polypropylene fibers

Cieślak

Schmidt

Twarowska-Schmidt

et al. 2017

Int. J. Environ. Sci. Technol.

View full text Add to dashboard Cite

Textile materials, because of their specific character, can affect the content of volatile pollutants in the indoor air, including the constituents of tobacco smoke (ETS-environmental tobacco smoke). Polypropylene fibers have a particularly high susceptibility for the sorption of nicotine. Textiles made of polypropylene are often used in different rooms or offices. The aim of the research was to give polypropylene fibers the photocatalytic properties by modifying their surface, using titanium dioxide doped with nanoparticles of silver (TiO 2 /Ag). Modification of polypropylene fibers with TiO 2 /Ag increases their susceptibility to sorption of nicotine and accelerates its decomposition. A comparison of the decomposition rate constants for the modified and unmodified fibers shows that the decomposition process runs from 1.6 to 2.9 times faster for the modified fibers depending on the nature of modification, the source of the nicotine and the ambient conditions. It was also found that the strength of modified fibers does not change under irradiation.

show abstract

Field Performance Test of an Air-Cleaner with Photocatalysis-Plasma Synergistic Reactors for Practical and Long-Term Use

Cited by 11 publications

References 21 publications

Improved Photocatalytic Air Cleaner with Decomposition of Aldehyde and Aerosol-Associated Influenza Virus Infectivity in Indoor Air

Improved Photocatalytic Air Cleaner with Decomposition of Aldehyde and Aerosol-Associated Influenza Virus Infectivity in Indoor Air

Plasma Oxidation of H2S over Non-stoichiometric LaxMnO3 Perovskite Catalysts in a Dielectric Barrier Discharge Reactor

Removal of nicotine from indoor air using titania-modified polypropylene fibers: nicotine decomposition by titania-modified polypropylene fibers

Contact Info

Product

Resources

About