Speciation Analysis of Chromium Using Cryptand Ethers

Abstract

The speciation analysis of chromium was studied using sequential solvent extraction of Cr ^III and Cr ^VI (previously reduced to Cr ^III ) with cryptand 2.2.1 as the ligand and eosin as a counter ion, in combination with spectrofluorimetry. A linear working range from the detection limit (1 ng ml ^{- 1} ) to 150 ng ml ^{- 1} of chromium was obtained. The proposed method was successfully applied to the determination of Cr ^III and Cr ^VI in sea-water and chromium in certified coal samples.