One of the ways to define yield is by the fraction of the solute in the feed that is ending up in the final product. The fraction of solute in the feed that remains in the solution can then be considered as the loss.
The crystal structure, size, shape and purity can be used to express the particle product quality of a crystalline product. Customer and manufacturer specification for a crystalline product can usually be related to these four product quality aspects. The crystal structure for instance impacts properties such as solubility, shelf life and bioavailability of a pharmaceutical compound. A crystal size distribution gives information on the collection of crystal sizes in the product, which is for instance an important parameter in determining the dissolution behavior of fertilizers and pharmaceuticals. The crystal shape can be vital for flow and storage properties of a product. In the food, pharmaceutical and fine chemical industries high levels of purity are desired. For instance, impurities from side reactions during the synthesis of an active pharmaceutical ingredient could lead to unwanted additional biological activity of the administered drug if they end up in the final product. Analytical techniques can be employed to measure and control particle product aspects throughout the manufacturing process.
Process parameters have a strong impact on the particle product quality. By understanding the relationship between process parameters and particle characteristics, manufacturers can optimize their processes to consistently produce high-quality particle products. A higher supersaturation during a crystallization process might for instance lead to a larger nucleation rate and therefore more particles and a product with a smaller average size. However, a higher supersaturation speeds up crystallization, increasing productivity.