ASTM D4438 – Standard Test Method for Particle Size Distribution of Catalysts and Catalyst Carriers by Electronic Counting
Description:
Significance and Use
4.1 This test method can be used to determine particle size distributions for material specifications, manufacturing control, and research and development work in the particle size range usually encountered in fluidizable cracking catalysts.
Scope
1.1 This test method covers the determination of particle size distribution of catalyst and catalyst carrier (see Terminology D3766) particles using an electroconductive sensing method and is one of several valuable methods for the measurement of particle size.
1.2 The range of particle sizes investigated was 20 μm to 150 μm (see IEEE/ASTM SI 10) equivalent spherical diameter. The technique is capable of measuring particles above and below this range. The instrument used for this method is an electric current path of small dimensions that is modulated by individual particle passage through an aperture, and produces individual pulses of amplitude proportional to the particle volume.
ASTM D4434