3.7. Effects of coexisting ions
The effect of common coexisting ions on the thallium retention
onto TiO2 nanoparticles was evaluated using the developed
method. The existence of coexistence ions would affect the
preconcentration of thallium by competitive adsorption. In
these experiments, various foreign cations and anions at
various concentrations were added to 1.5 lg L1 Tl(I) at pH
9 and enriched in microcolumn according to the recommended
procedure. The tolerance limits of the coexisting ions,
defined as the largest amount making the recovery of Tl(I) less
than 95%, were given in Table 1. It can be seen that the
presence of coexisting ions at a much higher level has no obvious
effect on the adsorption of Tl(I) ion under the selected
conditions.
3.8. Analytical performance of the method