Particle size is one of the most important characteristics of particulate materials. It directly affects many material properties, from the accessibility of minerals during processing, to the absorption kinetics of drugs, and the mouthfeel of foods. In industry, the aim of particle size measurement is first and foremost to find a correlation between the particle size distribution and the property of interest (e.g., mouthfeel, reactivity, bioavailability, sintering behavior, etc.). This information can then be used to modify the manufacturing processes that impact particle size and, ultimately, to use particle size distribution as a quality control parameter.
Thanks to modern instrumentation, measuring the particle size distribution of a substance is an easy and straightforward task, which can often be performed in less than a minute. A large variety of techniques are available, which deliver an equally large variety of results in the form of means, averages, modes, and other parameters. The key to understanding the results is to first know the meaning of these parameters.
In this article, we introduce the basic terms and their use in particle size analysis and discuss the advantages and disadvantages of using single parameters vs. multiple parameters to characterize particle size distribution.