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One of the causes for the aging of membranes during their operation in electrodialysis (ED) of solutions is irreversible chemical changes in the ion exchange or reinforcement polymer due to interaction of H
+
and OH
−
ions (present in feed solutions or generated in the membrane system under intense current modes) with the matrix or fixed groups in the surface layer of the membranes. The reduction in current efficiency and an increase in energy consumption in the process of electrodialysis are usual consequences of these changes. It has been shown that the degradation of the ion-exchange polymer on the surface of the CMX membrane during its operation in intense current regimes results in the hydrophobization of the membrane surface, which, in turn, causes enhancement of electroconvection. As a result, the limiting current and the mass transfer coefficient of salt ions increase during membrane operation. In the case of desalination of dilute solutions, this growth can reach 50–70% in comparison with the fresh membrane.