Computation of Isobaric Vapor-Liquid Equilibrium (VLE) Data of Methyl Tert-Butyl Ether (MTBE) + Acetic Acid (AA) System

The chemical and biological pathways for acetic acid production involve the separation of acetic acid from water. Azeotropic distillation and liquid-liquid extraction are used to separate acetic acid from water with conventional solvents, as simple distillation is impractical due to pinch point near the water edge and requires more energy to separate these two components. Methyl tert-butyl ether (MTBE) is a more viable solvent due to its low energy consumption during recovery. To compute isobaric vapor-liquid equilibrium (VLE) data for a binary mixture of methyl tert-butyl ether (MTBE) + acetic acid (AA) system, the group contribution method, UNIFAC was used. The thermodynamic consistency tests such as Redlich and Kister's and Wisniak's L-W were used to check the validity of these data. Wilson, UNIQUAC, and NRTL excess Gibbs energy models were used to determine the binary interaction parameters of these models. VLE data obtained in this work can be used to design the distillation and extraction system to recover and purify MTBE.