A comparison of automated scanning electron microscopy (ASEM) and acoustic attenuation spectroscopy (AAS) instruments for particle sizing

•Two independent particle sizing instruments yield similar particle size distributions.•Particle size distributions in the vendor specified range for standard materials.•Statistical comparisons demonstrate importance of comparing statistical significance. The objective of this work is to compare particle size distributions (PSD) measured by automated scanning electron microscopy (ASEM) and acoustic attenuation spectroscopy (AAS) instruments at Oklahoma State University (OSU). The techniques provide quantitative PSD measurements of dispersed systems of both hard and soft particles. Glass spheres, fly ash, and latex spheres are chosen to illustrate the range of materials that can be analyzed with these techniques. The variety of length scales and material property attributes investigated provides some insight about the consistency of the ASEM and AAS measurements for these types of particles. Although both instruments yield internally consistent PSD, rigorous statistical analysis shows that the two instruments can yield different results when measuring samples from the same batch of particles. The difference is not surprising given the different physics of each instrument. Nevertheless, the similarity in PSD hints at the validity of comparing absolute PSD and PSD changes.