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Unformatted text preview: II-1Catalyst surface•In order to catalyze a reaction, the reacting gases or liquids must come into contact with the surface of the heterogeneous catalyst. In general, the more the catalyst surface area available for reaction, the better.•Heterogeneous catalysts are typically porous materials with relatively high specific surface areas -- surface areas in the 100 to 500 m2/g range are common. Almost all of this surface area is internal, which means reactants must diffuse into the interior of the catalyst to find catalytic surface with which to interact.•Just one pound (about a handful) of a catalyst with a specific surface area of 100 m2/g will have a total surface area equivalent to 18 football fields.II-2Catalyst adsorptionCollision and sticking to the surface (adsorption)may modify the preexponential factor A.Adsorption on nonporous solidAdsorption on porous solidWhether by increasing the rate of production underthe same conditions or by making milder the operatingconditions, catalysts translate to savings in capitalcosts and operating costs.II-3...
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- Spring '09
- Catalysis, Langmuir isotherm