In order to assess the selectivity of the developed methodology,
the influence of several foreign species, usually presents in biodiesel,
was evaluated. Samples containing a fixed amount of iron
(40 lg L1) and increasing concentrations of the species under
evaluation were analyzed by the developed methodology. A compound
was considered as non-interfering if the analytical signal
variation was ±3% regarding the one obtained in its absence. Under
the used reaction parameters, the results (Table 3) showed that no
significant interfering effect for the majority of the tested compounds
was found. These results confirmed that the proposed
method is appropriate for the analysis of iron in biodiesel samples