Conductimetric detection of anions of very weak acids by incomplete suppressed ion chromatography

Abstract

A novel method, incomplete suppressed conductimetric detection, has been developed for the determination of anions of very weak acids. The principle of the method was discussed. Theoretical considerations involved the choice of background conductance and its effect on linearity and detection limits. Results showed that for both arsenous acid and boric acid, the sensitivity was improved greatly with low background conductance, compared with the suppressed conductimetric method. With 250 mg / l boric acid, there were 261-and 1002-fold increases in peak height and peak area, respectively. Within the linear range of the detection, quantified by peak areas, the linear correlation coefficients were 0.9991 and 0.9985 for arsenous acid and boric acid, respectively.

Simultaneous Determination of Arsenite and Arsenate in Arsenic Trioxide Injection by Dual Detection Ion Chromatography

“…Incomplete suppressed IC is discussed by Huang et al (46). He suggested to operate the suppressor in a mode such that the eluent is just barely neutralized, so that the arsenite will remain in an ionic state.…”

Two-Dimensional Detection in Ion Chromatography: Sequential Conductometry after Suppression and Passive Hydroxide Introduction

“…Caliamanis et al have developed an altogether different approach. A commercial suppressor unit bearing cation exchange membranes and an NaOH−EDTA external bathing solution is used to convert HX to NaX. − Yuan et al suggested operating a suppressor in a mode such that the eluent is just short of completely neutralized. However, it is very difficult to maintain such operation with a constant background, low-noise environment.…”