Abstract

Cobalt Determination In Fresh Waters Using Flow Injection With Luminol Chemiluminescence Detection

Author(s): A.Waseem, Shaheen Wali, Huma Asif

A simple and rapid and portable flow injection method is reported for the determination of Co(II) in fresh waters based on luminol CL detection in the absence of added oxidant. The detection limit (3s) was 0.1 nM with a sample throughput 60 h-1. Under the optimum conditions the method provided a linear range for Co(II) between 1.0 - 10 nM (r2=0.9986) with relative standard deviations (R.S.D) (n = 4) in the range 1.2 - 2.1%. The effect of interfering cations (Na+, Ca(II), Mg (II) , Zn(II), Cu(II), Fe(II), Fe(III) and anions (Cl-, SO4 2-, PO4 3-,NO3 -,NO2 -) were studied on luminol CL system for Co(II) determination. The method was applied to spiked fresh water samples and the satisfactory recoveries were obtained (97±0.10% - 105±0.10%).