The active transport of potassium ion through the sulfonated macroreticular poly(styrene-co-divinylbenzene) membrane was investigated using a diaphram cell. Potassium ion could be actively transported against its concentration gradient owing to the carrier functions caused by tautomerism of the sulfonic acid group in the membrane.
The active transport in this system, where one side of the membrane in the diaphram cell was acid and the other alkaline, was influenced by the amount of porogenic agent (tert-amylalcohol) and crosslinking agent (divinylbenzene). As the amount of tert-amylalcohol was decreased, the extent of transport of potassium ion was increased. On the other hand, the effect of the amount of divinylbenzene was negligible. It was presumed that the active transport through the membrane was effectively carried out in the micropore within the membrane and was dependent on the ion exchange capacity in the micropore.
In the selective transport of potassium and sodium ions, the selectivity was inversely proportional to the radius of the hydrated ion.
