5. Conclusions
A novel MACC technology was developed and comprehensively investigated to realize the automatic and accurate control of thiourea cooling crystallization, which governed by the heterogeneous nucleation and automatic screening on the PTFE and PES hollow fiber membrane interfaces. With effective interfacial heat transfer, the mechanism of membrane interface induced nucleation and process control was fully validated via the nucleation research and on-line monitoring. The overwhelming performance of MAAC reflects as dominating the accurate nucleation kinetic and hindering the secondary nucleation effectively, which resulting in the high purity, desire product morphology and very narrow CSD compared to that of conventional cooling crystallization (both artificial seeding and spontaneous nucleation operations were compared). Space-time process decoupling via surface nucleation in the membrane module and crystal growth in crystallizer, which is the core feature of the developed MACC, is a novel path for accurate crystallization control and process intensification.