Effect of Key Operating Parameters on the Retention and Separation of Ions Using Cyclical Electrical Field Flow...

The analysis of inorganic ions is critical in the environmental, industrial, and medical fields, with ion chromatography (IC) being the most used method. While IC offers high accuracy and reproducibility, its high cost, complexity, and operational constraints necessitate the development of alternative methods. This study explores the application of CyElFFF, a variant of electrical field-flow fractionation, for ion retention and separation. The CyElFFF with channel dimensions of 25 μm height, 10 cm length, and 0.5 cm width was developed, incorporating a conductivity detector and CO₂ suppressor. Parameters affecting retention time and separation resolution, including injection volume, ion concentration, and electric field conditions, were evaluated. Results showed enhanced ion retention and separation resolution at lower ion concentrations and optimized electric field settings in mode III. Separation of K⁺, Na⁺, NO₃^-, and SO₄^2- was demonstrated with separation resolution improved by reducing frequency and flow rate. These findings establish CyElFFF as a promising approach for ion analysis.