Heterogeneous Batch Extractive Distillation of Minimum Boiling Azeotropic Mixtures

Ivonne Rodriguez-Donis (1, 2) , Jhoanny Acosta-Esquijarosa (1) , Vincent Gerbaud (2) , Xavier Joulia (2)

1 Centro de Quimica Farmacéutica
2 LGC - Laboratoire de Génie Chimique

Following previous studies on heterogeneous batch azeotropic distillation, we evaluate the use of heterogeneous entrainers for the separation of binary azeotropic mixtures by extractive distillation. This process is well suited for systems where the entrainer forms a saddle heteregeneous azeotrope with anyone of the original components, such systems being unsuitable for non extractive heterogeneous batch distillation processes. Process feasibility is assessed from the isovolatility curves and the volatility order diagram. It tells us whether the homogeneous original component or the heteroazeotrope is drawn at the column top and establishes the distillation tasks sequence using a batch rectifying column. The theoretical insights are validated via rigourous simulation for the separation of the mixture acetonitrile – water with hexylamine or butyl acetate. Finally, the same method is applied for the theoretical analysis of a reported industrial example where water is used for the separation of binary organic mixture leading to a complex ternary system with several binary azeotropic points and a homogenous ternary azeotrope.

Mots clés: Batch distillation; Extractive distillation; Heterogeneous entrainer

Domaines: Génie chimique

Ivonne Rodriguez-Donis, Jhoanny Acosta-Esquijarosa, Vincent Gerbaud, Xavier Joulia. Heterogeneous Batch Extractive Distillation of Minimum Boiling Azeotropic Mixtures. AIChE Journal, 2003, 49 (12), pp.3074-3083. ⟨10.1002/aic.690491209⟩. ⟨hal-00467480⟩