S. Ninan et al., Camphor-3-thioxo-2-oxime as an analytical reagent for extractive spectrophotometric determination and separation of lead, SPECT ACT A, 55(4), 1999, pp. 825-831
Citations number
30
Categorie Soggetti
Spectroscopy /Instrumentation/Analytical Sciences
Journal title
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
Camphor-3-thioxo-2-oxime (HCTO) is proposed as a new sensitive analytical r
eagent for the extractive spectrophotometric determination of trace amounts
of lead. The method is based on the instantaneous formation of a stable ye
llow-orange colored 1:2 chelate with lead at room temperature in the pH ran
ge 9.3-9.6 selectively extracted in carbon tetrachloride. The extracted spe
cies exhibits an absorption maximum at 400 nm with a molar absorptivity of
4.14 x 10(4) mol(-1) cm(-1), complying with Beer's law over the concentrati
on range 0.1-0.5 mu g ml(-1) of lead with an optimum concentration range 0.
18-0.37 mu g ml(-1). The effects of pH, concentration of reagent and saltin
g-out agents, time of equilibration, order of addition of diluents and the
tolerance limit of the method towards various cations and anions usually as
sociated with lead are reported. The developed method is successfully used
for the determination of traces of lead in synthetic mixtures, alloys and o
re samples. (C) 1999 Elsevier Science S.A. All rights reserved.