Quantitative Comparison of the Most Common Particle Sizing and Surface Area Measurement Methods

Six different commercial subsieve powders were used for examining the effects of particle characteristics on mean particle size and specific surface area. The measurements were carried out using the air permeability and laser light diffraction techniques. The experimental data indicate that both methods give similar results for spherical powders. The advantage of laser light systems over gas permeameters is the ability to provide additional information on the particle size distribution. Irregularly-shaped powders should be analysed by both techniques relying on gas permeametry for surface area measurements and on laser light diffraction for the estimation of mean particle size and size distribution. Application of scanning electron microscopy as a complementary technique was found helpful in interpretation of data through visualization of individual particles.