Enhancing Nucleation using a Vortex-based Hydrodynamic Cavitation Device: Application to Antisolvent Crystallization of Paracetamol - Methanol - Water System.

Nucleation is the onset of the crystallization process, and enhancing its rate is fundamental to intensifying crystallization, be it in a batch or continuous mode of operation. The present work investigates, for the first time, the influence of hydrodynamic cavitation (HC) on enhancing the nucleation rate of paracetamol crystallization in a methanol-water system. Initially, the experiments were performed in a batch mode to determine the induction time using a vortex-based HC device (VD). The experimentally determined induction time was found to decrease with supersaturation. The use of HC was found to enhance nucleation and significantly reduce induction time. An appropriate correlation to estimate induction time is developed. Based on these findings, the VD-based continuous nucleator using a loop configuration was developed to intensify the performance of a continuous oscillatory baffle crystallizer (COBC). The VD-based nucleator improved the yield and productivity of the COBC, significantly reducing the risk of encrustation and clogging in the bends of the COBC. The approach and results presented in the current study will provide a sound basis for harnessing VD-based hydrodynamic cavitation for enhancing nucleation and intensifying antisolvent crystallization.