Simultaneous determinations of Cr(VI) and Cr(III) by ion-exclusion/cation-exchange chromatography with an unmodified silica-gel column.
In order to characterize the ion-exclusion and cation-exchange properties of an unmodified silica-gel column, the retention behaviors of Cr(VI) and Cr(III) ions were investigated using a Develosil 30-5 (150 x 4.6 mm i.d.) in the acidic region. Cr(VI) was separated from other anions by an ion-exclusion and ion-adsorption mechanism, and Cr(III) was separated from other cations with a cation-exchange mechanism. When using 2.0 mM oxalic acid (pH 2.6) as an eluent, a good separation of Cr(VI) and Cr(III) was obtained using conductimetric detection in 12 min. The method was successfully applied to the simultaneous determinations of Cr(VI) and Cr(III) added into tap-water and river-water samples.
Hirata
Shizuko
S
Graduate School for International Development and Cooperation, Hiroshima University, 1-5-1 Kagamiyama, Higashi-hiroshima 739-8529, Japan. hirata09@hiroshima-u.ac.jp
Kozaki
Daisuke
D
Sakanishi
Kinya
K
Nakagoshi
Nobukazu
N
Tanaka
Kazuhiko
K
D002852:Chromatography, Ion Exchange; D002857:Chromium / Q000032:analysis*; D005782:Gels / Q000737:chemistry; D019815:Oxalic Acid / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis*
D005782:Gels; D014874:Water Pollutants, Chemical; D002857:Chromium; D012822:Silicon Dioxide; D019815:Oxalic Acid