PARTICLE SEPARATION AND SIZE CHARACTERIZATION BY SEDIMENTATION FIELD-FLOW FRACTIONATION

This chapter provides, first, an overview of particle characterization by field-flow fractionation (FFF) and describes how FFF works, the applicable size range, the properties that can be characterized, and the underlying theory. Second, a number of applications of sedimentation FFF are shown to illustrate the applicability of this FFF technique to diverse particulate materials in both submicron and supramicron size ranges. The materials examined include uniform and broad latex populations, dense inorganic and metallic particles, elongated Teflon particles, and plate-like clay particles. It is shown that self-consistent particle size distributions can be obtained under different experimental conditions and that narrow fractions can be collected and further examined and characterized by microscopy or other means. The high speed of steric FFF is illustrated by a one minute run of 3-15-mu-m copper particles.