The Role of Molecular Thermodynamics and Simulation in Natural Gas Sustainable Processes

摘要

Advances in applied statistical mechanics and molecular thermodynamics together with the unprecedented increase of computing power over the last two decades have made molecular simulation a powerful tool for the elucidation of molecular mechanisms and microscopic phenomena and subsequent prediction of macroscopic physical properties of complex chemical systems of interest to oil and gas industry. A realistic atomistic representation of the intra- and intermolecular interactions in these systems results in predictions that are of comparable accuracy with experimental measurements. This work focuses on molecular dynamics simulation for modeling novel elastomer polymers with promising properties as membranes for natural gas mixture separation. A systematic investigation is presented regarding the chemical structure of silicon containing polymers and its effect on solubility, diffusivity and permeability of gases and liquids in these polymers. For such purposes, a detailed atomistic model was developed that accounts explicitly for intra- and intermolecular interactions. Bond stretching, bond angle bending, torsional angle displacement, repulsive and attractive dispersion interactions are accounted using models parameterized to quantum mechanics calculations and experimental data. The agreement between experimental data and molecular simulation predictions for the properties calculated ranges from good to excellent.