| This thesis consists of two subjects, penetration of a coating fluid into paper and molecular simulation of pillared clays and adsorption of multicomponent gas mixture in them.; The first part, discusses the characterization of the microstructure of the paper, and penetration of a coating fluid into a paper which is used in the paper and labelmaking industries. We have developed a novel method for characterization of the microstructure of a paper. The method, which is based on analyzing computer images of the microstructure, allows one to characterize it in terms of the size distribution of flow passages between the fibers of paper and connectivity of such passages, both in the planes of the fibers and in the direction perpendicular to the planes. We then compute the effective permeability tensor of a paper and investigate its dependence on the microstructure of a paper.; The second part, dedicated to the pillared clays as an adsorbent for mixture of gases. Molecular sieves are widely used in chemical and petrochemical industries a's catalysts, adsorbents, and membranes. Pillared clays are a new class of molecular sieve-like materials with a pore-size ranging from 6 to 40 Angstrom. Pillared clays are synthesized by extending the interlayer of the clay minerals with variety of large cations. Among these Al13-pillared montmorillonite can be used in conventional processes as adsorbent, catalysts and membranes. We have developed a novel microstructural model of these materials, as well as a new statistical mechanical theory of adsorption of a multicomponents gas mixtures in them. We have also carried out extensive molecular simulation of adsorption and separation of gas mixtures in these materials. Using the theory, we establish a link between the adsorption isotherms in the ternary mixtures and those of the single gases and two-component mixtures of the same gases. The predictions of the theory are compared with the experimental data, as well as the results of our molecular simulations for Al oxyhydroxy ion pillars. Excellent agreement is found between the predictions of the theory, the experimental data, and the results of molecular dynamics simulations.* (Abstract shortened by UMI.); *This dissertation is multimedia (contains text and other applications not available in printed format). The CD requires the following system requirements: Adobe Acrobat. |
