Catalytic Spectrophotometric Determination of Vanadium by Flow Injection Analysis

Determination of trace amount of vanadium in water was studied by flow injection analysis. Catalytic spectrophotometric detection was performed with bromate oxidation of o-phenylenediamine and by addition of tiron as an activator and also as a masking agent. Vanadium can be determined with sample rate of ca. 60–70 samples/hour with in a range of 0.01 ppm to 0.5 ppm V and with r.s.d. 0.555% for 0.1 ppm V and 0.37% for 0.3 ppm V. Interference by Fe(III) can be reduced by using 0.3% NH₄F as a carrier solution.