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Solving complex anion separation problems with a carbonate-hydrogencarbonate gradient.

Rakesh Bose·Raaidah Saari-Nordhaus·James M Anderson
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Abstract

This paper describes the application of a new suppressor to solve complex anion separation problems with carbonate-hydrogencarbonate gradients. In addition to suppressing the mobile phase and enhancing the analyte signal like any other ion chromatography suppressor, the new DS-Plus suppressor removes carbonic acid from the suppressor effluent when carbonate-hydrogencarbonate mobile phases are used. This greatly reduces the background signal, enabling carbonate-hydrogencarbonate gradients. Since carbonate-hydrogencarbonate mobile phase has stronger eluting power than hydroxide or tetraborate, only dilute concentrations are needed to separate most anions. By adjusting the carbonate-hydrogencarbonate ratio in the mobile phase, various anion mixtures including those containing organic and inorganic anions with -1 to -3 charges can be separated on one or two columns, eliminating the needs for columns with special selectivity.

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AnionsBicarbonatesCarbonatesJournal Article

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Rakesh Bose, Raaidah Saari-Nordhaus, James M Anderson. 2002-05-17. Solving complex anion separation problems with a carbonate-hydrogencarbonate gradient.. https://doi.org/10.1016/s0021-9673(01)01578-3

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