Determination of anion impurities in barium carbonate by ion chromatography with membrane treatment

An ion chromatographic ( IC) method with membrane treatment was developed for the simultaneous determination of anions (F, SO 4 and NO 3) in barium carbonate. The cation exchange membrane was applied in providing H in hydrochloric acid to dissolve barium car⁃ bonate and to prevent anions dissolving into the solution from hydrochloric acid. After pre⁃treat⁃ ment by acid dissolution and membrane treatment, the sample was diluted for 100 times and fil⁃ trated by a 0? 22 μm membrane, then analyzed by IC using 20 mmol / L KOH as the eluent. The target anions were separated by an Ion Pac AG11⁃HC (50 mm×4 mm) and an Ion Pac AS11⁃HC (250 mm × 4 mm) ion⁃exchange columns and detected by suppressed conductivity detection with 50 mA current. Under the optimized separation conditions, the calibration curves showed good linearity (R≥0? 999 6) in the range of 0? 01-5? 00 mg / L. The limits of detection were in 第 5期 朱彬和,等:膜处理⁃离子色谱法测定碳酸钡中的杂质阴离子 the range of 1? 37-9? 45 μg / L with the relative standard deviations (RSDs) of 1? 87% -2? 19%. The recoveries of F, SO 4 and NO 3 anions were between 84? 0% and 106? 2% . This method can determine the three inorganic anions (F, SO 4 and NO 3 ) in barium carbonate fast and accu⁃ rately. It is suitable for the simultaneous separation and detection of trace inorganic anions in insoluble products.