This application note describes the use of ion-exchange or ion-exclusion chromatography for the determination of five classes of compounds of interest to the brewing industry, including: carbohydrates, alcohols, organic acids, inorganic anions, and inorganic cations. One of two forms of electrochemical detection is used, pulsed amperometry or conductivity detection. This part of the application note describes the inorganic anion analysis which uses conductivity detection. This was formerly Dionex AN46.

This application note details a new method developed to quantify low levels of perchlorate. A large loop injection (1000 μL) is used with a Thermo Scientific™ Dionex™ IonPac AS11 column and suppressed conductivity detection to quantify perchlorate in drinking water down to approximately 2.5 μg/L. The method outlined in this application note allows the determination of low-µg/L (ppb) levels of perchlorate. A linear concentration range has been established to accurately quantify perchlorate in drinking water and ground water samples. (Note- Refer to AN134 and AU148 for more recent applications)

This work describes an IC method using a Dionex ICS-3000 system with IonPac AS18 anion-exchange and CS12A cation-exchange columns, electrolytically generated hydroxide and methanesulfonic acid eluents, and suppressed conductivity detection to simultaneously measure the common anions and cations in water samples obtained from desalination processes. This IC method supports all the monitoring needs of a desalination facility because it can measure anions in diverse matrices ranging from seawater to drinking water.

This study demonstrates the Thermo Scientific Dionex IonPac AS27 anion-exchange column for determination of trace concentrations of chlorite, bromate, chlorate, and bromide in drinking water samples. The Dionex IonPac AS27 offers several key advantages over the Dionex AS19 column, including the ability to determine trace bromate in the presence of the EDA preservative, good resolution of dichloroacetate (DCA, a surrogate anion) from potentially interfering matrix anions, and improved resolution between bromate and chloride.

A direct injection method was designed using a Reagent‑Free™ Ion Chromatography (RFIC™) system with in-line sample cleanup to accurately and reproducibly measure oxalate in Bayer liquor. The online sample preparation removes most of the aluminum so that it does not contaminate either the column or suppressor. Fluoride is used to promote ligand exchange with oxalate for aluminum. This online sample preparation method allows an accurate, reproducible, and rugged determination of oxalate in Bayer liquor.