Analytical Sciences
Online ISSN : 1348-2246
Print ISSN : 0910-6340
ISSN-L : 0910-6340
Original Papers
Indirect Spectrophotometric Determination of Small Amounts of Selenium(IV) and Arsenic(V) by Simple Extraction Using Flotation Columns
Gamal Abd El-Hafeez MOSTAFAShaban El-Syed GHAZY
Author information
JOURNALS FREE ACCESS

2001 Volume 17 Issue 10 Pages 1189-1193

Details
Abstract

A simple, rapid and selective procedure for the indirect spectrophotometric determination of Se(IV) and As(V) has been developed. It is based on the reduction of Se(IV) to Se(0) and As(V) to As(III) with hydroiodic acid (KI + HCl). The liberated iodine, equivalent to each analyte, is quantitatively extracted with oleic acid (HOL) surfactant. The iodine-HOL system exhibits its maximum absorbance at 435 nm. The different analytical parameters affecting the extraction and determination processes have been examined. The calibration graphs were found to be linear over the ranges 5 - 120 and 0.25 - 20 ppm of Se(IV) and As(V), with lower detection limits of 2.5 and 0.15 ppm and molar absorptivities of 1 × 104 and 0.5 × 104 dm3 mol-1 cm-1, respectively. Sandell’s sensitivity was calculated to be 0.0078 and 0.0149 µg/cm2 in the same order. The relative standard deviation for five replicate analyses of 40 ppm Se(IV) and 4 ppm As(V) were 1.0 and 0.9%, respectively. The proposed procedure in the presence of EDTA as a masking agent for foreign ions has been successfully applied to the determination of Se(IV) in a reference sample and As(V) in copper metal, in addition to their determination in spiked and polluted water samples.

Information related to the author
© 2001 by The Japan Society for Analytical Chemistry
Previous article Next article
feedback
Top