STUDY OF THE RECOVERY OF COLLOIDAL PARTICLES IN POTENTIAL BARRIER SEDIMENTATION FIELD-FLOW FRACTIONATION

Abstract

The recovery of particles of the colloidal components subject to separation by the potential barrier sedimentation field-flow fractionation (PBSdFFF) is of great significance in separation science. For the recovery studies in PBSdFFF, monodisperse submicron spherical particles of poly(methyl methacrylate) (PMMA) were used. The extent of the PMMA particles' adhesion and detachment on and from the Hastelloy C channel wall depends on the ionic strength of the suspending medium. The presence of the indifferent electrolyte of Ba(NO₃)₂ in the suspending medium, which influences the total potential energy of interaction between the PMMA particles and the channel wall, leads to the partial or total adhesion of the PMMA particles on the channel wall. Finally, the ideal experimental conditions for improving the recovery of the colloidal particles under study in PBSdFFF were investigated.

ACKNOWLEDGMENTS

The authors would like to pay tribute to the services of the late Professor J. Calvin Giddings, who supplied the SdFFF system, and to Miss A. Malliori for technical assistance.

This paper was presented at the Eighth International Symposium on Field-Flow Fractionation, September 6–8, 1999, Paris, France.