Understanding the phase behavior of mixtures is crucial to the successful design and operation of many chemical processes, particularly separation processes. Precise design and operation result in greater energy efficiency and better control. These requirements place ever greater demands on the ability of existing theories to correlate and to extrapolate experimental data. Many existing empirical correlations are not satisfactory for these applications. The best approach is to derive mixture theories from statistical thermodynamics which relate the thermodynamic behavior of substances to their molecular attributes. In addition to improved data correlation and extrapolation, these new theories offer the important advantage of serving as guides in selecting systems most appropriate for process requirements.
The research projects in my supervision fall primarily into two groups: computer simulation and molecular theory, occasionally complemented by appropriate experimental studies.
Computer simulation calculates numerically the macroscopic properties of systems with prescribed molecular interactions. These studies have been very successful in furnishing microscopic insight at the molecular level, providing semi- to quantitative data as well as in providing rigorous tests for approximate molecular theories; certain types of calculations require specialized techniques. Examples include the calculation of free energies and chemical potentials, simulations of near critical systems, and the calculation of transport properties in open systems. We have developed a number of new algorithms for such applications.