Non-Newtonian carriers in a batch electrophoretic cell with Joule heating:Hydrodynamic considerations and mathematical aspects

The Joule heating effects on hydrodynamics are examined for the case of a n on-Newtonian fluid flowing in a batch electrophoretic cell. The potential b enefits of using non-Newtonian fluids in electrophoretic separations could lead, for example, to an increase in the efficiency of separations and to a better scale-up of the operation for the processing of large quantities on a pilot or even an industrial scale. The analysis conducted in this resear ch is based on the formulation of simplified mathematical models that can c apture the most relevant aspects of the physics of the free convection that takes place in a batch electrophoretic cell. The first aspect is associate d with the carrier fluid when no solute sample (of particles or macromolecu les) is added to the device. This is, indeed, a carrier fluid completely fr ee of solute problem. This aspect of the research is referred to as the car rier fluid problem. The second aspect involved in the investigation is the analysis of the mass transport (i.e., convective-diffusive) process associa ted with the motion of a solute sample added to the carrier fluid. This par ticular aspect of the research is referred to as the solute problem of the free-convection electrophoretic cell. The two problems are sequentially cou pled and the solution of the carrier fluid problem must be performed first in order to have the velocity profile to study the solute problem. Details about hydrodynamic considerations and the solution approach are discussed i n this contribution.