Inorganic anions and cations in environmental waters were determined by ion chromatography. Stationary and mobile
phases were examined for the simultaneous separation of both anions and cations. Cations detection by UV detection
requires a mobile phase with a UV absorbing additive, which indirectly visualizes cations as negative peaks. Simultaneous
separation of anions and cations were achieved when using an eluent that consists of inorganic acid with weak basic amino
acid as additives. It was convenient to separate both anions and cations by coupling anion-exchange and cation-exchange
columns in tandem. The order of the separation columns connected affected the elution profiles. When the eluent comprises
of multiple anions and a single cation, the anion-exchange column should be connected in the upper stream, whereas when
the eluent comprises multiple cations and a single anion, the cation-exchange column should be connected in the upper
stream. Use of switching valves also allowed simultaneous separation of anions and cations in a single chromatographic run.
In the present work, operating conditions were optimized for the simultaneous separation of anions and cations.
2003 Elsevier Science B.V. All rights reserved.
Keywords: Water analysis; Inorganic anions; Inorganic cations