ABSTRACT CTS-9712138 K. Gubbin/Cornell Nanoporous solids find widespread use in the chemical, oil, pharmaceutical and food industries as adsorbents and membranes for separation processes and materials is largely empirical. The aim of this project is to provide more powerful methods, based in molecular theory and simulation, for prediction of adsorbed fluid behavior and for the design of improved processes. Modern statistical mechanical methods, including molecular simulation and kinetic theory, will b employed to carry our studies in three areas: 1. Phase separation in porous media will be studied by novel molecular simulation methods (including quench molecular dynamics, Monte Carlo with histogram reweighting, etc.). Three separate investigations are planned. The first will aim to model capillary condensation in well-characterized controlled pore glasses (CPG), for which high quality experimental data have been recently become available; a goal of this work will be to develop sophisticated models that will be useful in other CPG studies. The second will be a study of freezing and melting of fluids confined within nanoporous materials; systems studied will include the adsorbates neopentane, carbon tetrachloride, water and water/methane mixtures in carbons and oxides. The third project will be an examination of the importance of interpore correlation effects in inducing phase separation in small pore zeolites. 2. Selective adsorption of trace components in gas streams. Calculations will be made to elucidate the role of pore and system variables on the selective adsorption of trace contaminants in nitrogen and air streams for materials with pores of various geometries. The effect of the presence of water vapor on such selective adsorption on activated carbons will be studied to elucidate the mechanism for the large effects of humidity in industrial adsorption operations of this kind. The goal of this work is to develop methods for designing improved adsorbents for removal of trac e contaminants. 3. Diffusion in pores. Nonequilibrium molecular dynamics methods will be used to study mutual diffusion in mixtures in pores. The goal of this work will be to develop an understanding of the role of fluid-wall interactions, pore shape and size, and pore entrance effects on diffusion in real nanoporous materials.
