Simultaneous multi-element analysis of total As, Se and Sb on titanium dioxide by slurry sampling-graphite furnace atomic absorption spectrometry

A simple and rapid method for simultaneous determination of As, Se and Sb was studied by graphite furnace atomic absorption spectrometry (GFAAS). Titanium dioxide adsorbing As, Se and Sb was separated from sample solution (100 ml) with a membrane filtration (0.45 μm), and then prepared to be slurry (5.0 ml) by adding ultrapure water. The behavior and influence of titanium dioxide on determination of As, Se and Sb were investigated in this experiment. The optimal conditions of a furnace for these elements were chosen as follows: pyrolysis temperature was 150 °C, and atomization temperature was 2300 °C. The optimal conditions of adsorption for As, Se and Sb on titanium dioxide were listed: pH 2.0 in sample solution; 10 min of stirring time; and 20.0 mg titanium dioxide. The difference of the chemical valence of each element had no effect on the recovery of each element at the same optimal conditions. Limits of detection (3σ) for As, Se and Sb were found to be 0.21 μg l⁻¹, 0.15 μg l⁻¹ and 0.15 μg l⁻¹, respectively, with enrichment rate of 20, when 20 μl of slurry was injected into a Zr-coating tube. The proposed method was applied to tap water and river water.