Double-walled carbon nanotubes as a solid phase extractor for separation-preconcentration of traces of gold from geological and water samples

In this work, a solid phase extraction method has been developed using a column filled with double-walled carbon nanotubes (DWNT) for preconcentration-separation of gold(III) ions prior to their flame atomic absorption spectrometric determination. Gold(III) ions were quantitatively recovered on DWNT in 1.0 mol L-1 HCl. The influences of the analytical conditions including eluent type, sample volume, etc. on the recoveries of gold(III) ions were examined. The effects of concomitant ions were also investigated. The detection limits for gold(III) based on 3 sigma was calculated as 1.5 mu g L-1. The procedure presented in this paper was applied to the gold content of a number of water, geological and anodic slime samples with successful results.