Original scientific paper
https://doi.org/10.5599/jese.2014.0068
Voltammetric studies on mercury behavior in different aqueous solutions for further development of a warning system designed for environmental monitoring
Paul-Cristinel Verestiuc
; Faculty of Geography and Geology, Al. I. Cuza University of Iasi, 20 A. Carol I Bd., Iasi, 700505, Romania
Igor Cretescu
; Faculty of Chemical Engineering and Environmental Protection, Gheorghe Asachi Technical University of Iasi, 73, D. Mangeron Street, Iasi, 700050, Romania
Oana-Maria Tucaliuc
; Faculty of Geography and Geology, Al. I. Cuza University of Iasi, 20 A. Carol I Bd., Iasi, 700505, Romania
Iuliana-Gabriela Breaban
; Faculty of Geography and Geology, Al. I. Cuza University of Iasi, 20 A. Carol I Bd., Iasi, 700505, Romania
Gheorghe Nemtoi
; Faculty of Chemistry, Al. I. Cuza University of Iasi, 11, Carol I Bd., Iasi, 700506, Romania
Abstract
This article presents some results concerning the electrochemical detection of mercury in different aqueous solutions, using the following electrodes: platinum-disk electrode (PDE), carbon paste electrode (CPE) and glass carbon electrode (GCE). Using the voltammetric technique applied on the above mentioned electrodes, the experimental conditions were established in order to obtain the maximum current peaks, in terms of the best analytical characteristics for mercury analyses. The dependence equations of cathodic current intensity on the scan rate were established in the case of mercury ion discharge in each prepared solution of 0.984 mM HgCl2 in different electrolyte background: 0.1 M KCl, 0.1 M H2SO4 and 0.9 % NaCl. Among the three investigated electrodes, the carbon paste electrode presented the highest detection sensitivity toward mercury ions in the aqueous solution. It was observed that, at a low scanning rate, the pH had an insignificant influence over the current peak intensity; however, the quantification of this influence was achieved using a quadratic polynomial equation, which could prevent the errors in mercury detection in case of industrial waste stream pH changes. The calibration curves for mercury in 0.9 % NaCl solution and in the tap water respectively were carried out.
Keywords
Cathodic linear voltammetry; platinum electrode; carbon paste electrode; glass carbon electrode; mercuric ion; flow electrochemical cell
Hrčak ID:
130218
URI
Publication date:
6.12.2014.
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