TRANSPORT OF IONS ACROSS BIPOLAR MEMBRANES .2. MEMBRANE-POTENTIAL ANDPERMEABILITY COEFFICIENT RATIO IN CACL2 SOLUTIONS

The simulations and the experimental data of ionic transport across a bipolar membrane in dialysis systems of a 2-1 type salt, where ''2-1 t ype'' means a combination of a bivalent cation and a univalent anion, show that the transport properties of a 2-1 type salt in the system ha ve features different from those of a 1-1 type. (univalent cation and univalent anion) salt in the following points: (1) the potential of a 2-1 type salt system has a constant value irrespective of the charge d ensity ratio of the two charged layers when the membrane charge densit ies are much larger than the concentration of the salt solutions; (2) the potential-concentration curves have a peak under suitable conditio ns; (3) the permeability coefficient of the salt has a different value between two dialysis systems where the direction of the positive-nega tive layered structure of the membrane is reversed even if the mobilit y of the cation is the same as that of the anion.