Hostname: page-component-848d4c4894-tn8tq Total loading time: 0 Render date: 2024-07-04T18:34:34.486Z Has data issue: false hasContentIssue false

Spectrophotometric determination of low-level concentrations of Se in aqueous solutions

Published online by Cambridge University Press:  05 July 2018

A. Matamoros*
Affiliation:
Earth and Biosphere Institute, School of Earth and Environment, University of Leeds, Leeds LS2 9JT, UK
L. G. Benning
Affiliation:
Earth and Biosphere Institute, School of Earth and Environment, University of Leeds, Leeds LS2 9JT, UK
*

Abstract

This paper describes the design, testing and validation of a simple and inexpensive spectrophotometric method for total Se analysis in aqueous solution based on the azo coupling reaction of amines. In this reaction, selenite ions react with hydroxylamine hydrochloride (NH2OH.HCl), which in turn diazotizes p-Nitroaniline and is coupled with N-1-naphthyl-ethylenediamine dihydrochloride (NEDA) to form a red coloured azo compound. This azo compound has a maximum absorption peak at 545 nm, an apparent molar absorption of 2.85x104 l mol-1 cm-1 and it follows the Beer’s law in the range from 0.01 to 2.50 mg/l with R2 = 0.9998. Interferences between the azo reaction and non-targeted ions often present in environmental samples (i.e., NO3-, CO3-, Cl- or metals) were investigated and specific protocols to overcome them were implemented. The advantages of the new method for low levels of Se in aqueous solutions are its high sensitivity and reproducibility, and the fact that measurements are simple, rapid and low-cost.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2008

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Adkins, R.L., Walsh, N., Edmunds, M. and Trafford, J.M. (1995) Inductively coupled plasma atomic emission spectrometric analysis of low levels of selenium in natural waters. Analyst, 120, 1433–1436.CrossRefGoogle Scholar
Eaton, A.D., Clesceri, L.S., Greenberg, A.E. and Franson, M.A.H. (1998) Standard methods for the examination of water and wastewater, 20' edition. American Public Health Association, Washington, DC.Google Scholar
Holland, H.D. and Turekian, K.K. (2004) Treatise on Geochemistry. Elsevier/Pergamon, Amsterdam; London.Google Scholar
Martinez, L.D., Baucells, M., Pelfort, E., Roura, M. and Olsina, R. (1997) Selenium determination by HG-ICP-AES: Elimination of iron interferences by means of an ion-exchange resin in a continuous flow system. Analytical and Bioanalytical Chemistry, 357, 850–852.Google Scholar
Matamoros, A. (2002) Distribution espacial de selenio en suelos y su comportamiento geoquimico local al oriente de los municipios de Uticay Villeta. (Spatial distribution of selenium in soils and its geochemical behaviour in west Utica and Villeta municipalities). Facultad de Agronomia, Universidad Nacional de Colombia, Bogota.Google Scholar
Munoz, R., Donard, O.F.X., Camara, C. and Quevauviller, P. (1994) Analytical techniques applied to the speciation of selenium in environmental matrices. Analytica Chimica Ada, 286, 357–370.Google Scholar
Revanasiddappa, H.D. andKiran Kumar, T.N. (2001) A facile spectrophotometric method for the determination of selenium. Analytical Sciences, 17, 1309–1312.CrossRefGoogle ScholarPubMed
US EPA (2003) National Primary Drinking Water Standards. Environmental Protection Agency. EPA 816-F-03–016.Google Scholar
WHO (World Health Organization) (2003) Selenium in drinking-water. Background document for preparation of WHO guidelines for drinking-water quality. WHO, Geneva.Google Scholar
Zhu, J., Zuo, W., Liang, X., Li, S. and Zheng, B. (2004) Occurrence of native selenium in Yutangba and its environmental implications. Applied Geochemistry, 19,461–467.CrossRefGoogle Scholar