CASE STUDIES ON THE USE OF DISTILLATION IN THE PHARMACEUTICAL INDUSTRY

Within the pharmaceutical industry, distillation is generally utilized to efficiently remove one or more solvents or to exchange solvents in preparation for isolation of an active ingredient or intermediate. This chapter discusses the advantages and disadvantages of various modes of distillation along with practical considerations for implementing and optimizing distillation scale-up. It provides several examples of how distillation models have both provided deeper insight into a distillation process and enabled process design and scale-up. While distillation modeling can be used to fundamentally understand and design a robust process, the limitations of these models and processes must also be considered. The chapter also presents examples of using UNIFAC- vs. nonrandom two liquid-based models, enhancing distillation models with laboratory data, selecting distillation solvents to optimize distillation time and solvent usage, designing space optimization to control distillation time, and using distillation as a means of crystallization.