The Open Analytical Chemistry Journal
2012, 6 : 39-44Published online 2012 August 24. DOI: 10.2174/1874065001206010039
Publisher ID: TOACJ-6-39
Extractive Spectrophotometric Determination of Niobium (V) Using 3- Hydroxy-2-(4'-Methoxyphenyl)-4-Oxo-4H-l-Benzopyran as a Complexing Agent
University Institute of
Engineering & Technology, Kurukshetra University, Kurukshetra -136 119,
Haryana, India.
ABSTRACT
3-Hydroxy-2-(4'-methoxyphenyl)-4-oxo-4H-l-benzopyran (HMPB) forms a yellow colored (1:3) complex with niobium (V), which is extracted into dichloromethane from 1.04–4.40 molL-¹ HClO4 solution showing an absorption maximum at 398 – 412 nm (figure curve A: 1.0 μg Nb ml-1 versus blank; curve B: blank versus DCM) with Beer's law range of 0–1.3 μg Nb ml-¹, molar absorptivity of 3.764 x 104 L mol-1 cm-¹ and the detection limit as 0.036 μg ml-¹. The results are highly reproducible with a standard deviation of ± 0.0037. The linear regression equation is Y=0.399X + 0.006 and the correlation coefficient, r = 1.0004....