The particle size of powdered activated carbon is sometimes used to evaluate filter cake filtration rates and the filter penetration in filtering applications. The selection and handling of powdered activated carbon, and operation of processes using powdered activated carbon, requires the knowledge of the particle size.

Note 1—Relative humidity (RH) can affect the repeatability and accuracy of this test. Activated carbon not at equilibrium with the RH of the ambient air may lose or gain weight accordingly, dependent upon whether or not the carbon picks up or loses moisture.

1.1 This test method covers the determination of the particle size of powdered activated carbons using an air-jet sieve device. For purposes of this test method, powdered activated carbon is defined as activated carbon in particle sizes predominantly smaller than 80 mesh.

1.2 The values stated in SI units are to be regarded as the standard. The inch-pound units given in parentheses are for information only.

This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.