Na. Mishchuk et al., SUPERFAST ELECTROPHORESIS OF ELECTRON-TYPE CONDUCTING PARTICLES, Colloids and surfaces. A, Physicochemical and engineering aspects, 140(1-3), 1998, pp. 43-51
The features of concentration polarization caused by electric current
through a unipolar conductive particle are considered. The peculiariti
es of the formation of an induced space charge near a particle with el
ectron-type conductivity are analysed. It has been shown that the theo
retical values of electrophoretic velocity for these particles are ess
entially smaller than those calculated for particles with ion-type con
ductivity.A new method to observe the superfast electrophoresis is dev
eloped. The electrophoretic velocity of graphite and activated carbon
particles of different size (diameter, 200-500 mu m) displaced in dist
illed water and electrolyte solutions in strong electric fields (100-5
00 V cm(-1)) was measured. It is shown that, in contrast to classical
electrophoresis, the electrophoretic mobility of such particles increa
ses with the particle size and the external field strength. The experi
mental and theoretical results are compared. The discrepancy between t
heory and experiment is analysed. (C) 1998 Elsevier Science B.V. All r
ights reserved.