主讲内容：Crystallisation is an important unit operation used as separation and purification technique. It is widely employed in the pharmaceutical, chemical, agrochemical, food and cosmetics industries but also in the electronic, metallurgic and material industries. More than 90% of the active pharmaceutical ingredients (APIs) on the market are produced by crystallisation and crystal size, shape and lattice structure (polymorphism) have a profound effect on the properties of the final drug as well as on the efficiency of the downstream operations (filtration, washing, drying, tableting etc.). Therefore, monitoring and control this process is fundamental to ensure the quality of the end product. The implementation of process analytical technology (PAT) tools during the development stage of APIs has largely helped in better understanding and optimizing both batch and, more recently, continuous crystallisation. Specific instrumentation can be used to monitor on-line, in situ, crystal size and shape (focused beam reflectance measurement, FBRM, particle vision and measurement, PVM, ultrasound), polymorphism (Raman, FTIR and NIR spectroscopy) and liquid phase composition (Attenuated total reflectance UV/VIS and FTIR, on-line HPLC) [1-3]. Furthermore, feedback control strategies based on PAT tools signal can be implemented in order to specifically tailor the characteristics of the produced crystals and gain higher product quality and process efficiency [4,5]. This work shows few examples of application of PAT tools for the study and control of crystallization processes. Reference  Duffy, D., Barrett, M., Glennon, B. (2013) Cryst. Growth Des., 13, 3321–3332.  Povey, M. J. W. (2016) J. Chem. Phys., 145, 211906.  Wang, X., Watcher, J. A., Antosz, F. J., Berglund, K. A. (2000) Org. Process Res. Dev., 4, 391–395.  Simone, E., Saleemi, A. N., Tonnon, N., Nagy, Z. K. (2014) Cryst. Growth Des., 14(4), 1839–1850.  Simone, E., Zhang, W., Nagy, Z. K. (2015) Cryst. Growth Des., 15(6), 2908–2919.