Determination of Ni(II) and Co(II) by FAAS after preconcentration on modified alumina column

Abstract

A method for the determination of Co(II) and Ni(II) by flame atomic absorption spectrometry after preconcentration on a minicolumn of alumina modified with sodium dodecyl sulfate and

schiff's base has been developed. Effects of <i>p</i>H, flow rate, volume of sample solution, capacity of sorbent and interference of foreign ions on the recovery of the analytes have been investigated. Under the optimized conditions (<i>p</i>H = 5; flow rate =15 ml min^-1), recovery was greater than 98%. The relative standard deviations (10 replicate analyses) at the 50 ng ml^-1 level are 2.5% for Ni(II) and 3.2% for Co(II) and the corresponding limits of detection (3s,

n =10) are 0.014 ngml^-1 for Ni(II) and 0.007 ng ml^-1 for Co(II). The method has been applied for the determination of Ni(II) and Co(II) in natural waters and standard materials.