In this paper, the Nernst-Planck equation, in which the strong coupling eff
ects between the various species are considered by including electrical inf
luence produced by ion transfer, is introduced to the study of ion exchange
displacement chromatography and the solution of concentration distribution
is obtained for the steady state. In addition, the limitations of the orig
inal differential equations are also disscussed for the case of ion exchang
e displacement chromatography. (C) 1999 John Wiley & Sons, Ltd.