Photocatalytic reactor

Peill, N. J., and Hoffmann, M. R., 1995, Development and optimization of a Ti02 coated fiber - optic cable reactor Photocatalytic degradation of 4-chlorophenol, Env. Sci. Tech., 29 2974-2981. 

Besides improvements in catalyst characteristics [28], the low productivity of a photocatalytic process can also be improved by reactor design. In photocatalytic research on a laboratory scale, the most widely applied reactors are the top illumination or annular reactors containing a suspended catalyst [29]. This type of... 

The advantages of microreactors, for example, well-defined control of the gas-liquid distributions, also hold for photocatalytic conversions. Furthermore, the distance between the light source and the catalyst is small, with the catalyst immobilized on the walls of the microchannels. It was demonstrated for the photodegradation of 4-chlorophenol in a microreactor that the reaction was truly kinetically controlled, and performed with high efficiency [32]. The latter was explained by the illuminated area, which exceeds conventional reactor types by a factor of 4-400, depending on the reactor type. Even further reduction of the distance between the light source and the catalytically active site might be possible by the use of electroluminescent materials [19]. The benefits of this concept have still to be proven. 

We have developed a compact photocatalytic reactor [1], which enables efficient decomposition of organic carbons in a gas or a liquid phase, incorporating a flexible and light-dispersive wire-net coated with titanium dioxide. Ethylene was selected as a model compound which would rot plants in sealed space when emitted. Effects of the titanium dioxide loading, the ethylene concentration, and the humidity were examined in batches. Kinetic analysis elucidated that the surface reaction of adsorbed ethylene could be regarded as a controlling step under the experimental conditions studied, assuming the competitive adsorption of ethylene and water molecules on the same active site. 

Photocatalytic oxidation tests were performed in a photoreactor [2]. The flat, rectangular stainless steel reactor has dimensions of 578 mm x 113 mm and inlet/outlet ports at the two ends. The aerogel catalyst placed in a recess located at the center of the reactor was uniformly irradiated by... 

The prepared photocatal3rsts were tested to know the reactivity and quantum efficiency in the aqueous solution with trichloroethylene(TCE) as a reactant in photocatalytic batch reactor. Also these results were compared the reactivity to the case of P25 catalyst. The liquid phase photocatalytic reaction system was shown in Fig. 1. 

Photocatalytic oxidation of TCE in a Ti02-coated activated carbon fluidized bed reactor... 

Adsorption and photocatalytic oxidation of TCE with Ti02-coated activated carbon was also carried out in a cylindrical continuous flow fluidized bed reactor with 65cm height and 68cm inside diameter (Figure 1). 

Application of fluidized reactor in photocatalytic decomposition of gaseous acetic acid and ammonia... 

Hydrodynamic Analysis of a Novel Photocatalytic Reactor Using Computational Fluid Dynamics... 

Pareek, V.K., S.J. Cox, M.P. Brungs, B. Young, and A.A. Adesina, Computational fluid dynamic (CFD) Simulation of a Pilot-Scale Annular Bubble Column Photocatalytic Reactor. Chemical Engineering Science, 2003. 58(3-6) p. 859-865. 

The photocatalytic experiments were performed in a horizontal quartz tube which it have TiOi. Illumination was provided by 500 W mercury lamps, located above the horizontal quartz tube. The reactant was 0.1% (v/v) ethylene in air. In case of Photo-Catalyst test, reactor effluent samples were taken at 30 min intervals and analyzed by GC. The composition of hydrocarbons in the feed and product stream was analyzed by a Shimadzu GC14B (VZIO) gas chromatograph equipped with a flame ionization detector. In all case, steady state was reached within 3 h. 

Thus, photocatalysis and photogenerated catalysis indeed open up rather reach opportunities in fine organic synthesis, including some new reactions and nontraditional pathways for some known reactions. More efforts should be made in engineering of appropriate photocatalytic reactors for such synthesis. 

Previous research by our groiqD [6] has confirmed literature reports [1,2] that it is possible to photolyze methane, saturated with water vapcff, to produce methanol and hydrogen. In a modification of the above ejq)eriment, we were also able to photolyze methane sparged throu a photochemical reactor filled with water. Recently, we began investigating the photocatalytic conversion of methane in water. 

See also the theoretical description of a micro reactor for optical photocatalytic dissociation of non-linear molecules in [140]. Here, a mathematical model for a novel type of micro reactor is given. Rotating non-linear molecules at excitation of valent vibrations are considered, having a magnetic moment. Resonance decay of molecules can be utilized with comparatively weak external energy sources only. 

Fernandez-Ibaiiez, P., Sichel, C., Polo-Lopez, M.I., de Cara-Garcfa, M., andTello, J.C. (2009) Photocatalytic disinfection of natural well water contaminated by Fusarium solani using Ti02 slurry in solar CPC photo-reactors. Catalysis Today,... 

Ng, S.P. (2007) Visible-light-assisted photocatalytic degradation of gaseous formaldehyde by parallel-plate reactor coated with Cr ion-implanted Ti02 thin film. Solar Energy Materials and Solar Cells, 91, 54-61. 

Moziaa S, Morawskia AW, Toyodab M et al (2009) Application of anatase-phase Ti02 for decomposition of azo dye in a photocatalytic membrane reactor. Desalination 24 97-105... 

Natural nuclear reactors, 17 589 25 397 Natural organic polymers, manufactured fibers produced from, 24 616 Natural photocatalytic processes, in the environment, 19 100-101 Natural plant growth regulators, 13 22-28 Natural polymer hollow fibers, 16 23... 

Solar-grade silicon, production of, 22 507-508 Solar heat control, use of gold in, 12 703 Solarization effect, 19 203 Solar photocatalysis, 23 23-24 Solar photocatalytic detoxification, 19 76 Solar photocatalytic processes, 19 100-101 Solar photocatalytic reactor, using deposited titania, 19 99 Solar photoreactors, 19 95-99 Solar salt harvesting, 22 802, 806-808 Solar spectrum, 23 2 Solar still, 26 89-92 Solar thermal converters, 23 10-13 Solar transmittance, for thin films, 23 19 Solatene, 24 558 Solder, 3 53... 

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