Influence of Membrane Ion Sorption on Ammonium Transport in Donnan Dialysis with Cation Exchange Membranes.

ABSTRACT: Donnan dialysis (DD) is a promising approach for selectively recovering ammonium ions from wastewater, owing to its simplicity and low energy consumption. However, the role of ion sorption and desorption in cation exchange membranes (CEMs), particularly interactions between ammonium ions (NH₄ ⁺) and competing ions (e.g., sodium Na⁺), has often been overlooked. Our experimental results revealed a shift in the Donnan equilibrium caused by the preoccupied counterions in the CEM. For example, when the feed and draw solutions were in a 1:1 concentration ratio, the expected ammonium recovery efficiency was 50%. However, the NH₄Cl-presoaked membrane resulted in an increase of 19.1 ± 0.5% in the solution NH₄ ⁺ concentration and a de

SUBMITTER: Tang H 

PROVIDER: S-EPMC12910581 | biostudies-literature | 2026 Feb

REPOSITORIES: biostudies-literature