ABSTRACT
The corrected diffusivity is calculated in experimental studies where the transport diffusion is measured. Mass transport in microporous media takes place in an adsorbed phase. In the case of porous materials, diffusion is a very important topic, given that this effect is essential in catalysis, gas chromatography, and separation processes, as for example, for the description of mass transfer through the packed-bed reactors used in the chemical industries. In particular, porous inorganic membranes are made of alumina, silica, carbon, zeolites, and other materials and are generally prepared by the slip-coating method, ceramic technique, and sol-gel method. Porous zeolite-based membranes were prepared by applying the ceramic method by the thermal transformation of a natural clinoptilolite at 700°C–800°C. Zeolites and related materials are inorganic, microporous, and crystalline solids that are widely used in the chemical and the petroleum industries as catalysts, sorbents, ion exchangers, and cation conductors.
