Exchange Equilibrium through Ion Exchange Membranes Analytical Applications

Abstract

The high selectivity of modern ion exchange membranes is illustrated, and potential analytical applications to extraction and concentration of ionic substances are outlined. The distribution of cations at cation exchange equilibrium is described theoretically and verified experimentally. Extraction of cations through a cation membrane is favored by high ionic strength and by anionic complexers in the extractant solution. One-stage batch extractions can be made to exhibit losses below 1%. With simple apparatus, 100-fold enrichment in concentration is achievable experimentally. Limitations are stated. © 1966, American Chemical Society. All rights reserved.