Ion-association dispersive liquid- liquid micro extraction of ultra-trace amount of gold (III) in water samples using Aliquat 336 prior to Inductively Coupled Plasma Atomic Emission Spectrometry determination

A combined method with dispersive liquid- liquid micro extraction (DLLME) and ICP-OES has been developed for rapid separation, pre-concentration and determination of ultra-trace amount of gold (III). The extraction of the analyte was performed in the presence of a quaternary ammonium salt, N-Methyl-N,N,N-trioctyloctan-1-ammonium chloride, (Aliquat 336) as an extractant based on ion- association extraction system. 1-octanol and acetonitrile were used as extraction and disperser solvents, respectively. The variables affecting the extraction conditions were optimized. The calibration curve was linear in the range of 0.32-100 ng mL-1 with the detection limit of 0.09 ng mL-1, enrichment factor of 150 and extraction recovery of 74%. The precision (%RSD) of the method was 6.2% for 5 replicates and recoveries of 10 ng mL-1 Au (III). The accuracy of the method was verified by an add- found method. This sensitive, simple and fast method was successfully applied to the extraction determination of gold in tap, lake, mining water samples.

Keywords:

gold , dispersive liquid- liquid micro extraction , Aliquat 336 , Inductively coupled plasma atomic emission spectrometry