Paint, photocatalytic

The oxidative degradation of organic pollutants in water and air streams is considered as one of the so-called advanced oxidation processes. Photocatalytic decomposition of organics found widespread industrial interest for air purification (e.g., decomposition of aldehydes, removal of NO , ), deodorization, sterilization, and disinfection. Domestic applications based on Ti02 photocatalysts such as window self-cleaning, bathroom paints that work under illumination with room light, or filters for air conditioners operating under UV lamp illumination have already been commercialized. Literature-based information on the multidisciplinary field of photocatalytic anti-pollutant systems can be found in a number of publications, such as Bahnemann s [237, 238] (and references therein). 

Destruction by photocatalytic oxidation in the case of varying thicknesses of the paint film. 

The effect of initial NO concentration on the NO removal is shown in Fig. 8.22 Although the painted films and cement plates were less active than the PTFE sheets, these materials removed NO efficiently from environmental standard level to seriously polluted level (0.05-10 ppm). They were also able to remove N02 and S02 with similar efficiency. The lower efficiency at higher concentrations is explained by the rapid accumulation of reaction products (nitrate or sulfate) on the surface. Therefore, the photocatalytic method may not be suitable for treatment at emission sources. 

Laufs S, Burgeth G, Duttlinger W, Kurtenbach R, Maban M, Thomas C, Wiesen P, Kleffmann J (2010) Conversion of nitrogen oxides on commercial photocatalytic dispersion paints. Atmos Environ 44 2341-2349... 

Numerous articles of a general interest have appeared on photocatalytic chemistry. These include nanoparticles, protection of buildings, antibacterial properties, ageing of pigment blends, modified titanium dioxides, photocatalytic paints, stabilization of pigmented systems, sensitization of acid dyes " and clay masterbatches. Anatase has been found to have a detri-... 

Figure 22.4.9. VOC concentration from paint solvents as a fiinction of illumination time during photocatalytic treatment with a concentrating, parabolic trough, solar photoreactor.

Evstropov, A. A., Belyankin, 1. A., Krainov, N. V., Mikheeva, T. Ya., Kvasov, A. A., 1989, Catalytic Combustion of Gas emissions from A Spray-Painting Chamber , Lakokras. Mater. Ikh. Primen, Issue 1, pp. 115-118. Falconer, J. L. F. and Magrini-Bair, K. A., 1998, Photocatalytic and Thermal Catalytic Oxidation of Acetaldehyde on Pt/TiOj , accepted for publication in the Journal of Catalysis. 

For the past 20 years, the technology of TiO photocatalyst or photocatalysis has progressed rapidly, and become very attractive in the development of construction materials like ceramic tiles, blocks, glass, paints... with self-cleaning, air or water purification and antibacterial functions. As a result, various construction materials are being developed by utilizing the TiO photocatalysis. A broad list of possible applications of photocatalytic cementitious materials can be summarized as follows [11] ... 

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