Analysis of anions in alkaline solutions by ion chromatography after solid-phase extraction

An Ion Chromatographic (IC) method for the determination of six organic acids and three inorganic anions in alkaline solutions was reported. Formic, acetic, propionic, oxalic, succinic, glutaric acid, F-, Cl-, and SO4(2-) were separated and determined in 33 min. The analytes were removed from Bayer liquor by using an ion-exchange resin column. The chromatographic separation was achieved with only one IonPac AS11-HC column thermostated at 30 degrees C. Organic acids and inorganic anions were detected with a suppressed conductance detector. The precision results' showed that the repeatability and reproducibility were < 2.94 and < 1.37%, respectively. The accuracy of the method was assessed by the recoveries ranging from 86.3 to 105.6%. Under optimum conditions the detection limits ranged from 0.008 to 0.053 mg/l.