The Polystyrene-Divinylbenzene Stationary Phase Modified with Poly (Amine-Epichlorohydrin) for Ion Chromatography

A novel anion exchange stationary phase was synthesized based on polystyrene-divinylbenzene beads and poly (amine-epichlorohydrin) cationic polyelectrolyte. Epichlorohydrin and methylamine as monomers were used to prepare quaternized cationic polyelectrolyte and hyperbranched layers with a denser charged density and high hydrophilcity. Scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), Fourier transform infrared spectra (FTIR) and elemental analysis were utilized to characterize the particle surface and chemical composition of modified microspheres. The chromatographic evaluation was investigated by separating the analytes containing of common anions (fluoride, chloride, nitrate, phosphate and sulfate) and polarizable anions (iodide, thiocyanate and thiosulfate). High column efficiency was obtained with the plate number per meter up to 20,607 N/m for chloride. Fast separation of five common anions and three polarizable anions was accomplished within 11 min. Finally, the contents of thiosulfate in water reducing agent samples were determined with the homemade column. The linearity of the method was satisfactory over a concentration range of 5-120 mg/L with a correlation coefficient of 0.9972. The relative standard deviations were all less than 1.50% for retention time, peak height and peak area. The recoveries over the range of 93.67-116.15% were obtained by analyzing real spiked samples. The result suggested that the prepared stationary phase exhibited effective separation, desirable reliability and considerable stability for application in common anions and polarizable anions analysis.