New designed ion exchange-mosaic composite membrane (MM/AEM) was proposed in this study. The membrane was made from anionic exchange polymer gel (AEM) that coated onto mosaic polymer membrane to form AEM/MM polymer composite membrane system. Also, commercial ion exchange membrane was used as reference. The electrochemical properties of the composite membrane system (MM/AEM) and non-composite one (AEM) were investigated by chronopotentiometry measurements (CP) and current-voltage curves (I-V) . In the presence of KCl solution, the limiting current density of new designed composite MM/AEM was higher than that of commercial AEM. In other words, at the same current density, the transition time of composite AEM was shorter than that of commercial AEM, and also diffusion layer thickness, δ, of composite MM/AEM was smaller than that of commercial AEM. It can be concluded that the new designed composite anionic exchange membrane provides relatively good ion transport and other good membrane properties. In addition, the production of this composite membrane can be used in electrodialysis, as an alternative membrane.

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In the past, mercury electrolysis and diaphragm electrolysis were used for the manufacture of caustic soda and chlorine. In recent years however, due to growing concerns to prevent contamination of the environment, save energy and ensure a high grade of caustic soda purity, ion exchange membrane (IM) electrolysis is gaining popularity and being used more and more frequently all over the world.
In the case of the ion exchange membrane method, in particular, the brine itself must be of very high purity. By using a chelating resin we remove alkaline earth metal ions in brine.And we remove sulfate ion in brine by using amphoteric ion exchange resin. Then we introduce briefly the purification technology of using ion exchange resin for crude brine on IM electrolysis system.

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It is very important for development of PEM in PEFC to determine the proton conductivity and water vapor absorption amount. Unfortunately, when investigating these properties for the membranes, each data for them has been gotten by the each instruments and examined them by the researcher in spite of taking too much time. Hence, for the achievement of higher efficiencies to the polymer development, simultaneous measurement system (MSB-AD-V-FC^TM by BEL JAPAN Inc.) has been developed to achieve both properties to PEM in PEFC and DMFC under various experimental conditions (Temperature; 298-473 K, Humidity; 0-95%RH, Pressure; atmospheric pressure-1.0 MPa) . The upper mix-conditioned run to PEM enables in a single original chamber considering both principles of a gravimetric method for the water vapor absorption and an alternating current impedance method for proton conductivity and automatically proceeds by software, BEL-FCE^TM. Furthermore, we have found the high stable and reproducibility proton conductivity was achieved after the water vapor absorption equilibrium. We introduce our system as well as suggest the evaluation method for high reproducibility of proton conductivity using the system.

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