Electrochemical adsorption of perfluorooctanoic acid from aqueous solutions using ion exchange membranes

Perfluorooctanoic acid (PFOA) pollution in aqueous environments has become a matter of significant concern due to its adverse effects on the environment and ecosystems. In the pursuit of an efficient PFOA removal method, ion exchange membranes have been employed as adsorbents using the electrosorption technique. This study investigates the electrosorption capacity of PFOA, focusing on factors such as the types of ion exchange membranes, applied potential, residual time, and PFOA concentration. Among the various membranes tested, the polyvinylidene chloride membrane with quaternary ammonium groups demonstrated an impressive 92.5 % removal ratio under an initial concentration of 100 ppm. However, the desorption of PFOA poses a challenge due to its surfactant nature and the strong electrostatic interaction with the quaternary ammonium groups on the membrane surface. Our research findings indicate that using a protic CH 3 OH solution with NaCl enables efficient PFOA desorption. Additionally, the membrane exhibits a remarkable retention of 99.2 % capacity over five electrosorption-desorption cycles. In conclusion, the innovative electrosorption-desorption methods presented in this study offer a promising direction for effective PFOA removal.