BK1064-ch68_R2_250706 PRESSURE SWING BATCH DISTILLATION FOR HOMOGENOUS AZEOTROPIC SEPARATION

The separation of the homogeneous azeotropic mixture acetonitrile/water by pressure swing distillation (PSD) is considered. The PSD is operated as a discontinuous (batch) process and two batch modes, regular and inverted, are considered. The processes are analysed, aspects as to which batch mode should be preferred are discussed, and a dynamic model for both batch PSD processes is formulated. The model takes a cold and empty column as an initial condition. Because of the lack of experimental data, in particular for the inverted batch distillation, our own experiments were carried out. The regular and the inverted batch PSD consist of two steps, a low pressure and a high pressure run, and experiments are shown for every step. The simulations fit the experimental results with good accuracy.