Abstract Ion-macromolecule containing membrane dialysis systems widely exist in natural components and artificial communities. Donnan equilibrium is an ionic distribution balance law specially raised for ion-macromolecule containing membrane dialysis systems based on the electric potential. Although in a flat and direct expression, the definitions and explanations in Chinese textbook, as well as the applications in scientific studies, are in general open to doubt. This paper starts with bringing issues to these problematic descriptions. We completely divide and establish three ideal cases based on the existence of macromolecules, as "ion dialysis in" model system, "ion dialysis out" model system, and "macromolecule on both sides" model system. Then, we carefully calculate and discuss the mathematical processing together with the physical chemistry significance of each model system. Several pieces of limitations of Donnan equilibrium will be provided at last, hoping to facilitate the future education and research.
WANG A. Zhipeng. Modeling Calculation and Discussion on Donnan Equilibrium of Ion-Macromolecule Containing Semi-Permeable Membrane Dialysis Systems[J]. Chinese Journal of Chemical Education, 2017, 38(16): 19-25.
