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Catalyst coatings

Membrane Reactor. Another area of current activity uses membranes in ethane dehydrogenation to shift the ethane to ethylene equiUbrium. The use of membranes is not new, and has been used in many separation processes. However, these membranes, which are mostly biomembranes, are not suitable for dehydrogenation reactions that require high temperatures. Technology has improved to produce ceramic and other inorganic (90) membranes that can be used at high temperatures (600°C and above). In addition, the suitable catalysts can be coated without blocking the pores of the membrane. Therefore, catalyst-coated membranes can be used for reaction and separation. [Pg.443]

As an example of the selective removal of products, Foley et al. [36] anticipated a selective formation of dimethylamine over a catalyst coated with a carbon molecular sieve layer. Nishiyama et al. [37] demonstrated the concept of the selective removal of products. A silica-alumina catalyst coated with a silicalite membrane was used for disproportionation and alkylation of toluene to produce p-xylene. The product fraction of p-xylene in xylene isomers (para-selectivity) for the silicalite-coated catalyst largely exceeded the equilibrium value of about 22%. [Pg.219]

In this study, we developed microchannel PrOx reactor to control CO outlet concentrations less than 10 ppm from methanol steam reformer for PEMFC applications. The reactor was developed based on our previous studies on methanol steam reformer [5] and the basic technologies on microchaimel reactor including design of microchaimel plate, fabrication process and catalyst coating method were applied to the present PrOx reactor. The fabricated PrOx reactor was tested and evaluated on its CO removal performance. [Pg.654]

Haas-Santo, K., Eichtner, M., Schubert, K., Preparation of microstructure compatible porous supports by sol-gel synthesis for catalyst coatings, Appl. Catal. A 220 (2001) 79-92. [Pg.121]

P., Detailed characterization of various porous alumina based catalyst coatings within microchannels and their testingfor methanol steam reforming, Chem. Eng. Res. Des., special issue on Chemical Reaction Engineering (2003) submitted for publication. [Pg.249]

Catalyst Coating in Micro Channels Techniques and Analytical Characterization... [Pg.258]

Figure 3.12 Residence time distribution in a micro reactor which is tightened by different means. ( ) Glued reactor without catalyst coating (X) glued reactor with catalyst coating ( ) reactor with graphite joints. Calculated curves for tubular reactors with the Bodenstein number Bo = 33 (solid line) and Bo = 70 (dashed line). Figure 3.12 Residence time distribution in a micro reactor which is tightened by different means. ( ) Glued reactor without catalyst coating (X) glued reactor with catalyst coating ( ) reactor with graphite joints. Calculated curves for tubular reactors with the Bodenstein number Bo = 33 (solid line) and Bo = 70 (dashed line).
Activity of the same catalyst coating on different microstructured materials... [Pg.320]

Reactor performance with porous catalyst particles and porous walls that are catalyst coated... [Pg.622]

GL 16] [R 12] [P 15] By a plasma etch process (see description in ]R 12]), a highly porous surface stmcture can be realized which can be catalyst coated [12]. The resulting surface area of 100 m is not far from the porosity provided by the catalyst particles employed otherwise as a fixed bed. In one study, a reactor with such a waU-porous catalyst was compared with another reactor having the catalyst particles as a fixed bed. The number of channels for both reactors was not equal, which has to be considered in the following comparison. [Pg.622]

However, in view of the large specific surface area of catalysts used in conventional fixed-bed reactors for this reaction, attempts have to be made to realize catalyst coatings of similar porosity in micro channels [17]. [Pg.624]

Catalyst coatings on the reaction plate of a falling film micro reactor were prepared by four routes and tested [60]. [Pg.626]

In practice, the catal5Tic layers are prepared by brushing or spraying catalyst ink (a suspension of the catalyst particles in water and/or an organic solvent with addition of ionomer) either onto diffusion media (carbon paper or carbon cloth, also referred to as substrates), resulting in so-called catalyst-coated substrates (CCS), or directly onto... [Pg.517]

In the future it may be possible to reduce the cost by putting the catalyst coating directly on the PEM with a platinum-carbon ink, as practiced by Los Alamos National Laboratory. [Pg.3]

Next, the two temperature controllers were activated and the sandwich was taken up to 90°C (194°F) for one hour to evaporate the solvents from the liquid Nation 117 catalyst coating. The temperature was then raised to 130°C (266°F) over the next 30 minutes. This is the PEM glass transition temperature. [Pg.3]

Table 9.1. Preparation of V205/W03—Si02— Ti02 SCR catalysts coated on metal and cordierite substrates... Table 9.1. Preparation of V205/W03—Si02— Ti02 SCR catalysts coated on metal and cordierite substrates...
Tricot, Y.-M. and Fendler, J.H., Colloidal catalyst-coated semiconductors in surfactant vesicles In situ generation of Rh-coated CdS particles in dihexadecylphosphate vesicles and their utilization for photosensitized charge separation and hydrogen generation, /. Am. Chem. Soc., 106, 7359,1984. [Pg.281]

Another key part of a PEM membrane is the thin layer of platinum-based catalyst coating that is used. It makes up about 40% of the fuel cell cost. The catalyst prepares hydrogen from the fuel and oxygen from the... [Pg.267]

A small 3 cm x 3.5 cm section of the catalyst-coated desiccant wheel (25 cm diameter) was cut and placed in specially made holder shown in Fig. 12.9-6a. The piece of sample was tested in a 0.2 m3 environmental chamber at Chiaphua Industries Ltd. (Fig. 12.9-6b) for reduction of airborne VOC. The chamber was filled with the target VOCs through two stage saturators shown in Fig. 32b. Once the VOC level in the chamber stabilized, the fan was turned on to circulate the air through the sample. Three sets of sensors were located at the inlet and outlet of the holder, as well as in the center of the chamber. The chamber temperature and relative humidity were kept constant during the test. Figure 12.9-6c shows the results for VOC levels of 4000, 2000 and 1000 ppb at room temperature. The reduction rate was slower because of the low VOC concentration and the poor air circulation in the chamber. Also unlike the Prototype Unit, the catalyst was kept at room temperature throughout the test. [Pg.400]

After the six-month field test, the Prototype Unit was disassembled and the component parts were individually swabbed with sterilized cotton wools (4 cm2). Each samples were stored in 1 ml sterilized distilled water and 50 pi of samples were transferred to TSA and MEA plates. The TSA plates were incubated at 37 °C for 24 h and bacterial colonies were counted. The number of fungal colonies was determined from the MEA plates after incubating at 30 °C for 5 days. The results of the test are shown in Table 12.9-7. The results show that bacteria and fungi thrived near the air intake where they deposited on the grills, panel and around the intake slots. However once the microorganisms are drawn through the catalyst-coated desiccant wheel, the number of viable... [Pg.409]

M. K. Debe. Novel catalysts, catalyst supports and catalyst coated membrane methods. In Handbook of fuel cells Fundamentals, technology and applications. Vol. 3 Fuel cell technology and applications, ed. W. Vielstich, H. A. Gasteiger, and A. Lamm, 576 (2003). New York John Wiley Sons. [Pg.54]

There are two main types of thin-film catalyst layers catalyst-coated gas diffusion electrode (CCGDL), in which the CL is directly coated on a gas diffusion layer or microporous layer, and catalyst-coated membrane, in which the CL is directly coated on the proton exchange membrane. In the following sections, these catalyst layers will be further classified according to their composition and structure. [Pg.70]

Schematic diagram of MEA using Nafion gradient catalyst coating method. (Reproduced from Kim, K. H. et al. International Journal of Hydrogen Energy 2008 33 2783-2789. With permission from the International Association of Hydrogen Energy.)... Schematic diagram of MEA using Nafion gradient catalyst coating method. (Reproduced from Kim, K. H. et al. International Journal of Hydrogen Energy 2008 33 2783-2789. With permission from the International Association of Hydrogen Energy.)...
Catalyst layer ink can be deposited on gas diffusion layers to form a CCGDL, as discussed in the previous section. Alternatively, the catalyst ink can be applied directly onto the proton exchange membrane to form a catalyst-coated membrane (CCM). The most obvious advantage of the CCM is better contact between the CL and the membrane, which can improve the ionic connection and produce a nonporous substrate, resulting in less isolated catalysts. The CCM can be classified simply as a conventional CCM or as a nanostructured thin-film CCM. [Pg.76]

The nanostructured thin-film electrode was first developed at 3M Company by Debe et al. [40] and Debe [41], who prepared thin films of oriented crystalline organic whiskers on which Ft had been deposited. The film was then transferred to the membrane surface using a decal method, and a nanostructured thin-film catalyst-coated membrane was formed as shown in Figure 2.10. Interestingly, both the nanostructured thin-film (NSTF) catalyst and the CL are nonconventional. The latter contains no carbon or additional ionomer and is 20-30 times thinner than the conventional dispersed Pt/ carbon-based CL. In addition, the CL was more durable than conventional CCMs made from Pt/C and Nation ionomer [40]. [Pg.77]

Dry this catalyst-coated carbon paper for 24 hours in ambient air and then bake it at 225°C for 30 minutes to form an electrode. [Pg.82]

Dry the catalyst-coated membrane in a vacuum at a temperature of approximafely 160°C. [Pg.84]


See other pages where Catalyst coatings is mentioned: [Pg.277]    [Pg.503]    [Pg.293]    [Pg.77]    [Pg.654]    [Pg.99]    [Pg.121]    [Pg.258]    [Pg.274]    [Pg.319]    [Pg.637]    [Pg.334]    [Pg.518]    [Pg.246]    [Pg.65]    [Pg.50]    [Pg.96]    [Pg.68]    [Pg.97]   
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See also in sourсe #XX -- [ Pg.77 ]

See also in sourсe #XX -- [ Pg.86 ]




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Catalyst Carrier Coating Inside Bonded Reactors

Catalyst Coating Techniques

Catalyst Coating Techniques for Micro Structures and Their Application in Fuel Processing

Catalyst Coating in Micro Channels Techniques and Analytical Characterization

Catalyst carrier coating

Catalyst coated chip reactor

Catalyst coated membrane hydrophilic

Catalyst coated membrane hydrophobic

Catalyst coated membrane properties

Catalyst coated membrane requirements

Catalyst coated membrane technology

Catalyst coated semiconductor

Catalyst coating chemical vapor deposition

Catalyst coating electrochemical deposition

Catalyst coating electroless plating

Catalyst coating electrophoretic deposition

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Catalyst coating physical vapor deposition

Catalyst coating washcoating

Catalyst incorporation coatings

Catalyst layers coating RDE

Catalyst spray coating

Catalyst sputter coating

Catalyst wash coating

Catalyst wash-coated

Catalyst-coated diffusion

Catalyst-coated diffusion medium

Catalyst-coated gas diffusion electrode

Catalyst-coated membrane

Catalyst-coated membrane conventional

Catalysts for polyurethane coatings

Coated catalyst

Coated catalyst

Electrodes titanium, catalyst-coated, oxygen

Fabrication catalyst coating

Fuel coating catalyst

Interfacial catalysts, coated

Interfacial catalysts, coated electrodes

Micro-reactors catalyst coating techniques

Reactor catalyst carrier coating

Supported Catalysts Coated with Shell Layers

Urethane coating components catalysts

Wall-coated catalysts

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