Asphaltene migration and separation in presence of aggregation in electroosmotic–electrophoretic microchannel transport

In this paper, we provide a model to study the microchannel asphaltene transport and separation in presence of combined electroosmotic–electrophoretic transport and finite asphaltene aggregation effects. We invoke a perturbation-based analysis to develop analytical expressions for asphaltene band velocity (characterizing asphaltene electromigration) and separation resolution (characterizing separation of asphaltene species varying in aggregation or electrophoretic behaviors). We observe that the extent of the aggregation effects in affecting the asphaltene transport is strongly dictated by the nature of the electroosmotic–electrophoretic transport, and the net separation, too, is dictated by a non-trivial interplay of these two effects. Such coupled aggregation–advection–electrophoreting dynamics of asphaltene, in context of microfluidic transport, holds the key for understanding essential characteristics of asphaltene, relevant for its treatment during heavy oil upgrading.