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Photo-thermo-catalytic or PTC purification of process gasses (i.e., air, flue gases, and others) from NOx is presented in this study. A discussion of temperature's role in photocatalytic NOx removal and the progress of photo-thermo-catalytic reactors for the NOx removal process are presented. Lab- and pilot-scale reactors are described. The impact of temperature on the photocatalytic conversion of hydrocarbons is analyzed with regard to its relation to the photocatalytic selective reduction of NOx (photo-SCR). Another important issue is light transfer in pilot-scale reactors due to the sensitivity of light sources to temperature. Examples of light transfer solutions in photo-thermo-catalytic reactors are presented. Finally, the further development of photo-thermo-catalytic reactors is discussed, including pressurized systems. [ABSTRACT FROM AUTHOR]

ABSTRACT Visible-light absorbing TiO2 (vis-TiO2) and WO3 (vis-WO3) photocatalytic thin films were prepared by radio-frequency magnetron sputtering. The effect of heat treatment on thin film properties was investigated. Instrumental analyses such as X-ray diffraction, scanning electron microscopy-energy dispersive X-ray spectroscopy, and ultraviolet-visible absorption spectrometry were performed to reveal the crystallinity, surface morphology, chemical composition, and light absorption of the prepared thin films. To further enhance the photoactivity of the prepared thin films, a dual-layer photoelectrode (DLP) that consists of both vis-TiO2 and vis-WO3 was fabricated. Moreover, photoactivities of the prepared single and dual-layer photoelectrodes under both ultraviolet and visible-light irradiations were evaluated by conducting photovoltammetry as well as water-splitting reaction in an H-type reactor. It was demonstrated that the H2 and O2 yields obtained from water-splitting reaction are consistent with the photocurrent results, showing that DLP is more photoactive than single-layer photoelectrode. The enhanced performance of DLP is mainly attributed to the improved charge separation of the dual-layer structure. © 2012 Curtin University of Technology and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Plasmonic photocatalytic reactions have been substantially developed. However, the mechanism underlying the enhancement of such reactions is confusing in relevant studies. The plasmonic enhancements of photocatalytic reactions are hard to identify by processing chemically or physically. This review discusses the noteworthy experimental setups or designs for reactors that process various energy transformation paths for enhancing plasmonic photocatalytic reactions. Specially designed experimental setups can help characterize near-field optical responses in inducing plasmons and transformation of light energy. Electrochemical measurements, dark-field imaging, spectral measurements, and matched coupling of wavevectors lead to further understanding of the mechanism underlying plasmonic enhancement. The discussions herein can provide valuable ideas for advanced future studies. [ABSTRACT FROM AUTHOR]

The hydrophobic and spherical PDVB-x-MeCN (x: molar ratio of p-styrene sulfonate/divinylbenzene; x = 0.0, 0.1, 0.3, 0.5, and 1.0) catalyst was synthesized via polymerization and the ion-exchange process. Moreover, the hydrophobic property of PDVB-x-MeCN with high contact angles (> 124.0∘) was directly observed with a contact angle analyzer. The most appropriate x value of PDVB-x-MeCN for free fatty acid (FFA) removal and biodiesel production was 0.5, which was identified with gas chromatography (GC). During a 6-h transesterification-esterification, FFA removal and biodiesel yield of PDVB-0.5-MeCN reached 83.2% and 83.3%, respectively, at a ratio 45/1 (v/v) of methanol/palmitic acid mixture, approaching that of the Amberlyst 15 ones (83.4%). On the basis of these results, waste oils containing FFA can be transesterified efficiently from triglycerides and FFA into biodiesel. [Display omitted] • Waste palmitic oils with FFA can be effectively transesterified into biodiesel. • A hydrophobic PDVB-x-MeCN solid acidic catalyst with sphere shape was synthesized. • FFA removal efficiency can reach to 83.2% over PDVB-0.5-MeCN catalyst. • Optimal biodiesel yield of PDVB-0.5-MeCN was 83.4% after a 6-h transesterification. • EXAFS data reveals higher level of C8H7O3SNa may cause intramolecular defects and shrunk structure. [ABSTRACT FROM AUTHOR]