An electroanalytical application of 2-aminothiazole-modified silica gel after adsorption and separation of Hg(II) from heavy metals in aqueous solution


Autoria(s): Dias Filho, Newton L.; do Carmo, Devaney R.; Rosa, Andre H.
Contribuinte(s)

Universidade Estadual Paulista (UNESP)

Data(s)

20/05/2014

20/05/2014

12/11/2006

Resumo

2-Aminothiazole covalently attached to a silica gel surface was prepared in order to obtain an adsorbent for Hg(II) ions having the following characteristics: good sorption capacity, chemical stability under conditions of use, and, especially, high selectivity. The accumulation voltammetry of mercury(II) was investigated at a carbon paste electrode chemically modified with silica gel functionalized with 2-aminothiazole (SIAMT-CPE). The repetitive cyclic voltammogram of mercury(II) solution in the potential range -0.2 to + 0.6 V versus Ag/AgCl (0.02 mol L-1 KNO3; V = 20 mV s(-1)) show two peaks one at about 0.1 V and other at 0.205 V. The anodic wave peak at 0.205 V is well defined and does not change during the cycles and it was therefore further investigated for analytical purposes using differential pulse anodic stripping voltammetry in differents supporting electrolytes. The mercury response was evaluated with respect to pH, electrode composition, preconcentration time, mercury concentration, cleaning solution, possible interferences and other variables. The precision for six determinations (n = 6) of 0.02 and 0.20 mg L-1 Hg(II) was 4.1 and 3.5% (relative standard deviation), respectively. The detection limit was estimated as 0.10 mu g L-1 mercury(II) by means of 3:1 current-to-noise ratio in connection with the optimization of the various parameters involved and using the highest-possible analyser sensitivity. (c) 2006 Elsevier Ltd. All rights reserved.

Formato

965-972

Identificador

http://dx.doi.org/10.1016/j.electacta.2006.06.033

Electrochimica Acta. Oxford: Pergamon-Elsevier B.V., v. 52, n. 3, p. 965-972, 2006.

0013-4686

http://hdl.handle.net/11449/137

10.1016/j.electacta.2006.06.033

WOS:000242616100027

Idioma(s)

eng

Publicador

Elsevier B.V.

Relação

Electrochimica Acta

Direitos

closedAccess

Palavras-Chave #silica gel modified #preconcentration #heavy metals #carbon paste electrodes
Tipo

info:eu-repo/semantics/article