Distillation profiles in ternary heterogeneous mixtures with distillation boundaries

Distillation boundaries are created by saddle azeotropes and divide the composition space into distillation regions. In this study, the behavior of rectification profiles was investigated in the following heterogeneous systems: benzene, tert-butanol, water and ethanol, water, toluene. These systems were chose in order to scrutinize whether distillation regions overlapped. The experiments were performed using Distil (afterwards Conceptual Engineering) software from AspenTech, Inc. For each type of distillation column (staged and packed), a different pair of distillation boundaries is referred (TRB & PDB and SDB & PDB accordingly). Similar to homogeneous mixtures, distillation regions were found to overlap each other in heterogeneous mixtures. As a consequence, their common part was parametrically sensitive.

Figure optionsDownload high-quality image (206 K)Download as PowerPoint slideResearch highlights▶ There are three types of distillation boundaries—simple distillation boundary (SDB), total reflux boundary (TRB) and pitchfork distillation boundary (PDB). ▶ To each type of distillation column (staged or packed) a different pair of distillation boundaries is referred. ▶ Distillation boundaries divide the composition space into distillation regions. ▶ Distillation regions overlap one another in heterogeneous mixtures. ▶ Common part of distillation regions is parametrically sensitive.