Racemic resolution of propranolol in membrane contactors: Modelling and process optimisation

This work reports the study of the chiral resolution of propranolol, an amino-alcohol with proven efficacy in the treatment of hypertension, ischemic heart disease and arrhythmia. Among all β-blockers, propranolol was selected also due to the distinct properties of its enantiomers. Extraction and stripping kinetic studies were performed using a tubular module contactor, with ceramic ultrafiltration supporting membranes. Three different configurations were evaluated in terms of enantio-selectivity and enantiomeric excess of the desired enantiomer: (1) single extraction; (2) simultaneous extraction, where each enantiomer is preferentially recovered to a different extraction phase; (3) simultaneous selective extraction and stripping of a target enantiomer. The kinetic model developed, comprising an equilibrium modelling of the extraction process and differential mass balances in pseudo steady-state, fully describes the overall process. Moreover, the model allowed the optimisation of the operating conditions and enables to predict the optimum combination of module configurations in order to maximise the enantiomeric excess.