Search results for "Activated alumina"

Chromium speciation using activated alumina microcolumns and sequential injection analysis-flame atomic absorption spectrometry

2001

Abstract A new procedure has been developed for chromium speciation in water by sequential injection analysis and flame atomic absorption spectrometry. The method involves the online retention of Cr(VI) anionic species and Cr(III) cationic species on alumina microcolumns, prepared by packing activated alumina in polytetrafluoroethylene tubes, followed by selective elution of Cr(VI) with 2 mol l −1 NH 4 OH and of Cr(III) with 0.2 mol l −1 HNO 3 . Studies were carried out on the effect of retention and elution conditions for both Cr species. The limit of detection values, established as the concentration corresponding to three times the standard deviation of blank measurements divided by the …