THE THEORY FOR ZONE MIGRATION IN ELECTROCHROMATOGRAPHY

In electrochromatography, both a mobile phase and an electrical curren t pass through a column containing a stationary phase, Therefore, char ged eluites migrate through the column due to an electrophoretic and a chromatographic transport mechanism. In this paper, the mass balance equation for finite concentration differences is solved for charged el uites. Numerical examples are shown to illustrate the physical consequ ences of the obtained solution of the mass balance equation. The solut ion contains chromatographic and electrophoretic zone migration theory as limiting cases. In the general case, the mixing of chromatographic and electrophoretic transport mechanisms gives rise to strong nonline ar effects. These effects may cause strong band broadening or, alterna tively, a stabilized zone which does not change its form during the mi gration through the column.