CTS-9406702 Washington State University Cornelius F. Ivory Richard L. Zollars ABSTRACT The research deals with the development of a hybrid rotor for continuous field-flow fractionation (FFF). By combining conventional sedimentation with FFF in a two-dimensional system, a rotor whose selectivity is proportional to the square of the centrifugal field can be designed in principle. However, problems with flow instability have hindered the rotor development. The primary objective of the research is to establish whether the rotor can be operated without centrifugal instability. Linear stability theory will be used to determine the conditions for the onset of instability in terms of appropriate experimental parameters. If successful, large scale fractionation of submicron particles to high purity will become practical using FFF. This would then have a strong impact on separations technology for submicron particles, especially for bioprocessing applications.
