Dependence of composition of anion-exchange membranes and their electrical conductivity on concentration of sodium salts of carbonic and phosphoric acids

Concentration dependencies of electrical conductivity of AFN, AMX, ACS and ACM anion-exchange membranes (from Tokuyama Soda), equilibrated with solutions of sodium salts of carbonic and phosphoric acids as well as with sodium sulfate solutions, are studied. Analysis of the data on electrolyte desorption from the membranes equilibrated initially with solutions of the weak-acid salts as well as the application of the microheterogeneous model allowed to explain the change of the conductivity with a concentration growth by the effect of two factors: (i) a change (an increase, in the most cases) of the conductivity of the electroneutral solution forming the membrane ‘inter-gel’ phase, (ii) a variation of the conductivity of the membrane ‘gel’ phase caused by hydrolysis reactions of the weak-acid anions in the pore solution.