The zeolite H-type framework is flexible and additionally has the ability to adapt, and grow, to substrate surfaces. When adsorbed on a metal surface, the zeolite H-type framework is able to form a surface acid that is capable of dissociating water to remove aluminum from the zeolite, thereby regenerating the zeolite.
The zeolite P-type framework is rigid and does not have a direct ability to grow like the zeolite H-type framework. This means that the zeolite P-type framework is not able to adapt to the limits of the substrate surface. If the substrate surface is of the wrong geometry, a zeolite P-type framework will not form the appropriate structure to receive the maximum amount of substrate surface area.
Hydrogen-terminated zeolites are analogous to the carbons for oxygenates and alcohols, with similar selectivity and adsorption. The sodium based zeolite A becomes a much more selective substance because of this addition. Pentasil, or gamma-alumina, zeolite is used in thin-bed fixed-bed systems for fuel injection. The gamma-alumina is sintered into shape, and the shape is then fired to bond the granules. Inlet air preheats the bed and, because of its much higher heat capacity, removes heat from the bed. As the air passes through the bed, it passes the exhaust from the metal-oxide-semiconductor (MOS) cells on the opposite wall of the bed. The metal of the MOS conducts heat to the wall and is cooled. d2c66b5586