cloud point extraction of palladium as chelate with 1-(2-pyridylazo)-2-naphthol using triton x-114 prior to determination in real samples by etaas

A pre-concentration and determination methodology for palladium in real samples at ultra-trace levels by 1-(2-pyridylazo)-2-naphthol (pan) was developed. the analyte in the initial aqueous solution, acidified with hcl, was complexed with pan and triton x114 was added as a surfactant. the surfactant-rich phase was diluted with concentrated hno3 (65%, w/w) after phase separation. then, the concentrations of analyte were determined by graphite furnace atomic absorption spectrometry (gf-aas). the variables affecting the complexation and extraction steps were optimized. under the optimum conditions, namely a ph of 4.5, a cloud point temperature of 55 °c, the concentration of pan of 1.2×10^-4 mol l-1, 0.1% (w/v) triton x-114, a sample volume of 1.0 ml, (centrifuged at 3500 rpm) an enhancement factor of 26-fold was reached. triton x-114 allowed the detection limit of 0.01 ng ml−1 of pd. the precision measured as relative standard deviation (r.s.d.) for 10 replicate determinations at 10.0 μg l−1 pd was 2.5%. analytical graphs were rectilinear in the concentration range of 3200 μg l−1 and relative standard deviations were lower than 5%. the method affords recoveries in the range of 97 to 101%. the method