Catalytic coatings

One reason to use micro structured reaction chambers is certainly the possibility of describing the fluid dynamic behavior in these structures due to the laminar flow regime. With the following calculations the reactive gas flow in a square micro structure with coated catalytically active walls will be studied in detail. The task was to find a channel arrangement and to calculate the residence time distribution of this arrangement numerically (Figure 4.93). 

M. Arai, K. Yamada, and Y. Nishiyama, Evolution and separation of hydrogen in the photolysis of water using titania-coated catalytic palladium membrane reactor, 7. Chem, Eng, Jap, 25 761 (1992). 

Okahata, Y, Yamaguchi, M., Tanaka, F. T., and Fujii, I., A lipid-coated catalytic antibody in water-miscible organic solvents, Tetrahedron, 51, 7673-7680, 1995. 

Preparation of a V205-coated catalytic membrane by sol-gel method... 

The permeabilities of oxygen through the Vycor were constant with the pressure difference and decreased with the square root of the temperature (figure not included). So the main mechanism for gas permeation is Knudsen diffusion. However, the permeabilities of oxygen through the V20s-coated catalytic membrane were deviated from Knudsen diffusion. As the partial oxidation proceeded, the... 

The V206-coated catalytic membrane was applied to the partial oxidation reaction to produce maleic anhydride from 1-butene. The maximum selectivity was 95% at 350 °C and the permeability of oxygen through the V20s-coated catalytic membrane was enhanced. More careful studies are needed about this permeability enhancement. 

COATINGS CATALYTS ELECTRONIC PROTECTIVE CATALYST SUPPORTS FIBEROPTIC PREFORMS CONTROLLED PORE GLASS GLASSES ... 

Figure 3.21 Computations in a Pt-coated catalytic microreactor with length and height of 10 mm and 1 mm, respectively. (A) Ignition (t g) and steady-state (f t) times versus inlet pressure. Triangles ignition times circles steady-state times. Solid lines 90% CI-14/10% H2 fuel blend ( =0.37). Dashed lines 100% CH4 fuel ( =0.40). (B) Cumulative emissions of unburned methane. Adapted from Karagiannidis and Mantzaras (2012) (with permission).

The structure and properties of plasma polymers are closely connected with a thin-film form, in which they are produced. In general, the thickness of the films is between a few nanometers and a few micrometers. Appropriate choice of precursors and plasma process parameters allow for the preparation of such thin films with a huge variety of structure and properties. Hence, there is a wide and diverse range of their current and anticipated applications, such as electronic and photoelectronic materials, insulating coatings, catalytic films, semi-permeable and electrolyte membranes, protecting layers, and many others. Some of these uses are also related to the electrochemical systems. 

In Chap. 7, the investigation on combustion stabihty is extended to propane-fueled catalytic microreactors, using the catalytic and gas-phase chemical reaction schemes of propane combustion on platinum proposed and validated in Chap. 4. The steady hetero-Zhomogeneous combustion of lean propaneZair and methaneZair mixtures in a platinum-coated, catalytic plane channel-flow microreactor were investigated at pressures of 1 and 5 bar, channel heights of 1.0 and 0.3 mm, and wall thermal conductivities of 2 and 16 WZmK. Stability limits were assessed as a function of fuel type, inlet velocity, and imposed external heat losses. Parametric studies were performed with a full-eUiptic, two-dimensional numerical model employing detailed gas-phase (homogeneous) reaction schemes for both fuels. 

Catalytic cathodes in membrane cell operations exhibit a voltage savings of 100—200 mV and a life of about 2 + yr using ultrapure brine. However, trace impurities such as iron from the caustic recirculation loop can deposit on the cathode and poison the coating, thereby reducing its economic life. 

When the operating temperature exceeds ca 93°C, the catalytic effects of metals become an important factor in promoting oil oxidation. Inhibitors that reduce this catalytic effect usually react with the surfaces of the metals to form protective coatings (see Metal surface treatments). Typical metal deactivators are the zinc dithiophosphates which also decompose hydroperoxides at temperatures above 93°C. Other metal deactivators include triazole and thiodiazole derivatives. Some copper salts intentionally put into lubricants counteract or reduce the catalytic effect of metals. 

DIBK can be produced by the hydrogenation of phorone which, in turn, is produced by the acid-catalyzed aldol condensation of acetone. It is also a by-product in the manufacture of methyl isobutyl ketone. Diisobutyl ketone ( 1.37/kg, October 1994) is produced in the United States by Union Carbide (Institute, West Virginia) and Eastman (Kingsport, Teimessee) (47), and is mainly used as a coating solvent. Catalytic hydrogenation of diisobutyl ketone produces the alcohol 2,6-dimethyl-4-heptanol [108-82-7]. 

Fig. 13. Single-sheet diffusion transfer plate (a) stmcture (b) upon exposure to light (c) development and (d) washing off and finish. In (a) the plate is first coated with a receiver layer of small (<5 nm) catalytic sites. The photographic layer is a spectrally sensitized silver haUde emulsion. In (c) the exposed areas develop as silver metal. Unexposed areas diffuse down to the receiver layer and form the printing image. In (d) the emulsion is washed off, revealing...

RCF is sold in a variety of forms, such as loose fiber, blanket, boards, modules, cloth, cements, putties, paper, coatings, felt, vacuum-formed shapes, rope, braid, tape, and textiles. The products are principally used for industrial appHcations as insulation in furnaces, heaters, kiln linings, furnace doors, metal launders, tank car insulation, and other uses up to 1400°C. RCF-consuming industries include ferrous and nonferrous metals, petrochemical, ceramic, glass, chemical, fertiH2er, transportation, constmction, and power generation/incineration. Some newer uses include commercial fire protection and appHcations in aerospace, eg, heat shields and automotive, eg, catalytic converters, metal reinforcement, heat shields, brake pads, and airbags. 

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