EFFECT OF THE TEMPERATURE ON THE ELECTROOSMOTIC PERMEABILITY OF A CATION-EXCHANGE MEMBRANE

The water electroosmotic flux, J(v), through a cation exchange membran e has been measured as a function of the temperature, T, with various values of the electrolyte concentration and for different current dens ities. From these measurements the electroosmotic permeability, W, of the membrane has been determined under different experimental conditio ns. In the studied temperature range, 282 K less than or equal to T le ss than or equal to 308 K, a clear dependence of W on T was observed, so that, W decreases when T increases at the lowest values of T, where as the opposite behavior occurs at the highest values of T. For this r eason the (T, W) curves show a minimum in most of the studied cases. T he position of this minimum as well as the value of the minimum of the electroosmotic permeability depends clearly on the concentration and the current density. (C) 1997 Academic Press.