Abstract
It is wellknown that an ion flux is proportional to the difference of electrochemical potential between the ionic solutions which are separated by a simple physicochemical membrane. In this paper, the reverse ion transport coupled to chemical reaction was studied to explain the transport phenomena in terms of the membrane equation reported in the previous literatures.
The liquid membrane was prepared by dissolving 10-2mol·dm-3 octadecylamine hydrochloride in I-octanol, and it was supported into a membrane filter. This liquid anion exchange membrane showed an ideal potential response for Cl and OH- (Fig.2). The system, (HClsoln. )-(liquid membrane)-(NaCH-NaOH soln. ) having the same Cl- concentrations in two aqueous phases, was chosen as the reverse transPort system. The ion flux and membrane potential of the system were measured as a function of time (Fig.3 and 5). The reverse transport of Cl- driven by an acid-base reaction as well as the change in membrane potential were observed (Table 1).
Based on an assumption that acid-base reaction takes place very fast, the experimental results were reasonably explained according to our equations (Table 2). It was concluded that the acid-base reaction energy is transformed into the electrochemical potential and as a result, the reverse ion flux is driven by the difference in the electrochemical potential of Clbetween phases I and II.
