Pre-concentration of aqueous hexavalent chromium using tributyltin chloride immobilised on C18 cartridges

Abstract

Disposable commercial C₁₈ mini-cartridges are treated with tributyltin chloride (TBTCl) and used for selective pre-concentration of Cr^VI from aqueous solutions. The accumulated Cr^VI-TBTCl adduct is eluted with 5 ml of methanol and measured using electrothermal atomic absorption spectrometry. Pre-concentration factors of 100-fold are readily achieved for 0.100 ng ml^–1 samples of Cr^VI with an average recovery of 98 ± 8%.