Volume: 4, 2025
4th International PhD Student’s Conference at the University of Life Sciences in Lublin, Poland:
ENVIRONMENT – PLANT – ANIMAL – PRODUCT
Abstract number: E013
DOI: https://doi.org/10.24326/ICDSUPL4.E013
Published online: 9 April 2025
ICDSUPL, 4, E013 (2025)
Determination of Co(II) in the environmental samples by stripping voltammetry
Paulina Mrózek1*, Iwona Gęca1
1 Department of Analytical Chemistry, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie Sklodowska University, Marii Skłodowskiej-Curie 3, 20-031 Lublin, Poland
* Corresponding author: paulina.mrozek01@wp.pl
Abstract
Cobalt is a metal present in the industrial environment in the form of fumes and dust. It can be absorbed through the respiratory tract and cause chronic poisoning, leading to respiratory tract inflammation, cardiac and thyroid disorders. The increasing concentration of this metal in the environment requires constant monitoring. Various analytical methods are used for this purpose including stripping voltammetry. The studies were related to the use of a new type of solid bismuth microelectrode array, which can be an alternative for using commonly used toxic mercury electrodes. Furthermore, the application of the presented electrode does not require the addition of bismuth ions to the supporting electrolyte to form a bismuth film electrode, which is an additional environmental advantage. The research was conducted by adsorptive stripping voltammetry in a traditional three-electrode system using a new type of a solid bismuth microelectrode array as a working electrode, an Ag/AgCl/NaCl reference electrode and a platinum wire counter electrode. The measurements were performed from a solution containing 0.1 mol/L ammonium buffer of a pH of 9.4 and 5 × 10–4 mol/L nioxime as a complexing agent. The standard measurement procedure consisted of the following steps: the microelectrode activation took place at a potential of –3.0 V for 3 s. Then, at a potential of –0.7 V for 120 s Co (II) ions in the form of a complex with nioxime accumulate on the surface of the working microelectrode. Voltammogram was recorded with a change in potential from –0.7 V to –1.3 V. The linear range of the calibration curve was found to be in the concentration range from 5 × 10–10 to 1 × 10–7 mol/L. It was found that a 1000-fold excess of V(V), Cu(II), W(VI), Mo(VI), Fe(III), Mn(II), Zn(II) ions and a 10-fold excess of Pb(II) and Ni(II) ions in 1 : 1 ratio to Co(II) concentration did not interfere with the analytical signal of Co(II). The developed procedure was applied to determine Co(II) in river water samples from the Bystrzyca River. The correctness of the presented procedure was also confirmed by analysis of certified reference material TM 26.5 obtaining results consistent with the certified values. In conclusion, the developed analytical procedure with the application of a new type of solid bismuth microelectrode array can be used for the determination of Co(II) in real water samples by adsorptive stripping voltammetry.
Keywords: cobalt, determination, bismuth microelectrode array, stripping voltammetry, environmental monitoring
How to cite
P. Mrózek, I. Gęca, 2025. Determination of Co(II) in the environmental samples by stripping voltammetry. In: 4th International PhD Student’s Conference at the University of Life Sciences in Lublin, Poland: Environment – Plant – Animal – Product. https://doi.org/10.24326/ICDSUPL4.E013