Optimisation of volatile elements determination by flow injection hydride generation-inductively coupled plasma spectrometry in electrolytic manganese

The simultaneous determination of As, Hg, Sb, Se and Sn by flow injection hydride generation-inductively coupled plasma optical emission spectrometry (FI-HG-ICP-OES) can be performed in electrolytic manganese after this work. Volatile species were generated mixing acidified aqueous samples and sodium tetrahydroborate solution in a continuous flow system, and the chemical and instrumental conditions were optimised experimentally. In case of the instrumental variables, the optimisation was achieved following the experimental design approach, while the chemical variables were adjusted following the variation of the signals of the analytes. As a result, the simultaneous determination of all the analytes was achieved at the following conditions: power supplied (P = 1550 W), sample and argon flow rates (F = 4.75 ml min−1, G = 0.6 ml min−1), NaBH4 (≤1.0%) and HCl (=0.6 mol dm−3). The spectral interferences between the volatile elements and matrix effects were evaluated. Finally, different detection limits (w/w) were obtained for As (0.0006%), Hg (0.0008%), Sb (0.0008%), Se (0.0005%) and Sn (0.001%) with repeatability R.S.D. < 2.0% for all elements concentrations tried.