Toward development of activity coefficient models for process and product design of complex chemical systems

Molecular thermodynamics, an engineering science for quantitative representation of thermophysical properties and phase behavior for mixtures, has served as a core scientific foundation for process modeling and process and product design in the industries. This paper presents a personal adventure through molecular thermodynamics that follows the footprints of John Prausnitz and leads toward the development of activity coefficient models for process modeling and process and product design of complex chemical systems. In this scientific expedition, passion and endurance, industrial applications, molecular insights, and out-of-the-box thinking all play key roles. We venerate past accomplishments that serve industrial needs and cherish new opportunities that await future exploration by adventurous souls.