Modeling the ion transfer and polarization of ion exchange membranes in bioelectrochemical systems.
An explicit numerical model for the charge balancing ion transfer across monopolar ion exchange membranes under conditions of bioelectrochemical systems is presented. Diffusion and migration equations have been solved according to the Nernst-Planck Equation and the resulting ion concentrations, pH values and the resistance values of the membrane for different conditions were computed. The modeling results underline the principle limitations of the application of ion exchange membranes in biological fuel cells and electrolyzers, caused by the inherent occurrence of a pH-gradient between anode and cathode compartment, and an increased ohmic membrane resistance at decreasing electrolyte concentrations. Finally, the physical and numerical limitations of the model are discussed.
Harnisch
Falk
F
University of Greifswald, Institute of Biochemistry, Felix-Hausdorff-Strasse 4, Greifswald, Germany.
Warmbier
Robert
R
Schneider
Ralf
R
Schröder
Uwe
U
D001674:Bioelectric Energy Sources; D004058:Diffusion; D017097:Electric Impedance; D004566:Electrodes; D005465:Fluorocarbon Polymers / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007474:Ion Exchange; D008567:Membranes, Artificial; D008956:Models, Chemical; D013997:Time Factors
D005465:Fluorocarbon Polymers; D008567:Membranes, Artificial; C040402:perfluorosulfonic acid