Determination of Trace Vanadium(V) by Catalytic Kinetic Spectrophotometry

A new catalytic spectrophotometric method for determination of trace vanadium (Ⅴ), which was based on the catalytic effect of V(Ⅴ) on the oxidation of o phenylenediamine and gallic acid by potassium bromate, was proposed. The liner range was 0~0.025 μg·25 mL -1 of V(Ⅴ). The limit of detection was 1.18×10 -6 g·L -1 of V(Ⅴ),the rariation coefficient was 4.63 %(n=10).The regression equation is △A=25.66C(mg·25 mL -1 )-0.0157(r=0.9997),the molar absorbtivity coefficient was 3.27×10 -7 L·mol -1 ·cm -1 . The method has been applied to determine vanadium in water and food samples with satisfactory results.