Facile and Sensitive Spectrophotometric Method for the Determination of Vanadium

Highly sensitive and simple spectrophotometric method is described for the determination of vanadium(V) using a new reagent azure B. The method is based on the reaction of vanadium(V) with potassium iodide in an acidic condition to liberate iodine, the liberated iodine bleaches the blue color of azure B and is measured at 636 nm. The decrease in absorbance is directly proportional to vanadium concentration. The method obeys Beer’s law over a concentration range of 0.02–9.0 μgmL -1 vanadium . The molar absorptivity, sandell’s sensitivity, detection limit and quantification limit of the reaction system were found to be 4.33 × 10 4 L mol − 1 cm -1 , 0.0011 µg cm − 2 , 0.75 µg ml − 1 and 2.27 µg ml − 1 respectively. The optimum reaction conditions and other analytical parameters have been evaluated. The proposed procedure has been successfully applied to the determination of vanadium in water, soil, plant material, urine, pharmaceutical preparations and steel samples. The resul ts were compared to those obtained with the reference method.