Application of nanometer-size titanium dioxide in extreme-trace V(V) analysis

The adsorption properties of nanometer-size TiO 2 for V(V) were studied. The adsorption rate could reach above 99% when the pH values were at the range of 4–10. The adsorption balance time was 10 min, the saturation capacity of adsorption of nanometer-size TiO 2 to V(V) was 6.43 mg per gram. Using 2 mL 1. 5 mol·L −1 NaOH as elution, we found the elution rate could reach 95%. A novel method of extreme-trace V(V) preconcentration with nanometer-size titanium dioxide and determination by graphite furnace atomic absorption spectroscopy (GFAAS) was advanced. The detection limit (3σ) of the method was 0.61 μg· L −1 , and the relative standard deviation was 8.1% ( n =6) of 2.5μg·L −1 V(V). Environmental samples experiments were also conducted to test the feasibility of the method, and it came out that the recovery rates were between 91.2% and 102.0%.