서강대학교

초록 (요약문)

Reverse electrodialysis (RED) is an effective way to generate power by mixing two different salt concentrations in water using cation-exchange membranes (CEM) and anion-exchange membranes (AEM). Previously, we proposed a free-standing, extremely porous covalent organic framework membrane that is robust at high temperatures and under 100% hydration, which is used as CEM in reverse RED. This in-house CEM showed steady working performance but also provided a smaller power density compared to generally used commercial membranes, like CMV or CMX. This study presents the RED model using the Nernst Equation to find the optimal conditions to achieve the maximum RED performance with the in-house membrane. The RED model was validated by comparing analytical simulation with experimental measurement. It is found that the values from the RED model agree well with the experimental results under various measurement conditions. Through the simulation, the maximum net power density of 0.352 W/m2 was obtained with an optimal intermembrane distance of 0.2 mm and a flow rate of 4 mL/min. The increase in membrane area resistance of 37 Ω cm2 dropped the power density by 0.046 W/m2, while the increase in the membrane thickness changed only 0.008 W/m2. Since the influence of the membrane area resistance on the power density was much greater than the effect of the membrane thickness, this thesis suggests making a thinner in-house membrane to enhance the performance of the RED.