On the thermodynamics and rates of some membrane processes

A previously developed description of multi-process near-equilibrium systems in terms of individual kinetically independent processes is extended to some membrane processes. For the examples considered it is shown that this description is at least as convenient as the application of irreversible thermodynamics; for example, it leads to quite obvious criteria for “anomalous” osmosis. Moreover, irreversible thermodynamics does not properly describe systems in which solution leaks through the membrane. A by-product of the process description is that it aids in understanding equilibrium systems such as classical Donnan equilibria and the electromotive force of Donnan cells both with and without the separating membrane.