A highly selective and sensitive spectrophotometric determination of vanadium(III) using 3-hydroxy-2-(2-thienyi)-4H -chromen-4-one

Department of Chemistry, Kurukshetra University, Kurukshetra-136 119, India E-mail : Kuru @doe.ernet.in Fax : 91-01744-20277/21.639 Manuscript received 24 October 2000, revised 11 April 2001, accepted 20 April 2001 3-Hydroxy-2-(2-thienyI)-4H-chromen-4-one (HTC) forms a 1 : 1 (V : HTC) yellow complex with Vin species at 47-57º in 0.03-0.14 M CH3COOH medium which is extracted into CCI4 having a λmax at 420 nm. The molar absorptivity, Sandell's sensitivity and standard deviation are 7.45 x 104 dm3 mol-1 cm-1, 0.0007 µg V cm-2 and ±0.0012 absorbance unit, respectively. Beer's law is obeyed over the concentration range 0-0.85 gg V per ml. Presence of a large number of elements do not interfere. The method has good reproducibility and can be satisfactorily applied for the analysis of industrial samples