Optimal separation times depend heavily of the nature of the electro-advective flow within the micro-capillary channel. Many times, electrokinetic flows are coated-based suppressed to aid the separation and avoid mixing within the microchannel domain. With many microdevices such elimination may not be desirable since loading and other functions within the channel may be needing such flows. This research investigates the role of electrokinetic-based flows and determines potential favorable conditions for separations with their presence. Using the spatial-averaging method in combination with the solute species continuity equation, the authors have derived analytical expressions for effective parameters, i.e., effective dispersion coefficient and effective convective velocity. These mathematical expressions are useful for the study of optimal separation times for electrophoretic processes, such as electro-assisted drug delivery, micro-electrophoretic separations, soil remediation, and material processing where electro-advection is one of the driving force for the flow of solutes. Illustrations are presented to demonstrate the effect of different parameters in a capillary channel of rectangular geometry. The influence of applied electric field, surface potential and Debye length on the velocity profiles is examined and the implications for optimal separations times identified. Further research effort to include other geometries of the micro-device and experimental conditions are included.