Simultaneous spectrophotometric determination of chromium(VI) and iron(III) with chromogenic mixed reagents by H-point standard addition method and partial least squares regression

Authors
Citation
H. Abdollahi, Simultaneous spectrophotometric determination of chromium(VI) and iron(III) with chromogenic mixed reagents by H-point standard addition method and partial least squares regression, ANALYT CHIM, 442(2), 2001, pp. 327-336
Citations number
38
Categorie Soggetti
Spectroscopy /Instrumentation/Analytical Sciences
Journal title
ANALYTICA CHIMICA ACTA
ISSN journal
00032670 → ACNP
Volume
442
Issue
2
Year of publication
2001
Pages
327 - 336
Database
ISI
SICI code
0003-2670(20010905)442:2<327:SSDOCA>2.0.ZU;2-0
Abstract
Simultaneous determination of Cr(VI) and Fe(III) by partial least squares ( PLS) calibration and H-point standard addition method (HPSAM) is described. Mixed reagents of diphenylcarbazide and 1,10-phenanthroline in a non-ionic micellar solution of Triton X-100 was used as a selective chromogenic syst em for determination of Cr(VI) and Fe(III). The presence of a micellar syst em allows one to eliminate the previous solvent extraction step that is nec essary for the determination of slightly soluble metal complexes in the abs ence of micelles. This reduces the cost and toxicity of the method. The tot al relative standard error for applying the PLS method to 15 synthetic samp les in the ranges 0.20-6.00 mug ml(-1) Cr(VI) and 0.20-8.00 mug ml(-1) was 1.5%. The results of applying the H-point standard addition method showed t hat Cr(VI) and Fe(III) can be determined simultaneously with weight concent ration ratios of Cr(VI) to Fe(III) varying from 15:1 to 1:30 in the mixed s ample. Both proposed methods (PLS and HPSAM) were also successfully applied to the determination of Cr and Fe in several synthetic alloy solutions. (C ) 2001 Published by Elsevier Science B.V.