Spectrophotometric determination of vanadium using rhodamine-B

Chemistry Department, Govt. V.Y.T. College, Durg, Chhattisgarh, India school of Studies in Chemistry, Pt. Ravishankar Shukla University. Raipur-492 010, Chhattisgarh, India Manuscript received 22 November 2004. revised 20 October 2005, accepted 16 December 2005 A new reagent system using rhodamine-B dye for the determination of vanadium is described. The method is based on the reaction of vanadium with acidified potassium iodide to liberate iodine. The liberated iodine bleaches the pink colour of rhodamine-B. which is measured at 553 nm. Beer's law is obeyed over the concentration range of 2-16 μg of vanadium in finalsolution volume of 25 ml (0.08-0.64 ppm). The apparent molar absorvity and Sandell's sensitivity were found to be 1.3x 105 L mor1 cm-1 and 0.0009 μg cm-2 respectively. The method is simple, sensitive and satisfactorily applied to ppm level for the determination of vanadium in different environmental and biological samples.