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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

In situ redox speciation analysis of chromium in water by diffusive gradients in thin films using a DE81 anion exchange membrane

Texto completo
Autor(es):
Suarez, Carlos A. [1] ; de Simone, Thays V. [1] ; Menegario, Amauri A. [1, 2] ; Rolisola, Ana M. C. M. [1] ; Luko, Karen S. [1] ; Gastmans, Didier [1] ; da Conceicao, Fabiano T. [2] ; Kiang, Chang H. [1, 2]
Número total de Autores: 8
Afiliação do(s) autor(es):
[1] UNESP Univ Estadual Paulista, Ctr Estudos Ambientais, Ave 24-A, 1515, BR-13506900 Rio Claro, SP - Brazil
[2] UNESP Univ Estadual Paulista, Inst Geociencias & Ciencias Exatas, Ave 24-A, 1515, BR-13506900 Rio Claro, SP - Brazil
Número total de Afiliações: 2
Tipo de documento: Artigo Científico
Fonte: Talanta; v. 154, p. 299-303, JUL 1 2016.
Citações Web of Science: 5
Resumo

A method for the in situ redox speciation analysis of chromium in water by the diffusive gradients in thin films (DGT) technique using a DE81 anion exchange membrane was successfully developed. For the selective uptake of Cr(VI), a DGT device containing an anion exchange membrane DE81 (cellulose acetate chromatographic paper) was used (DE81-DGT), while selective uptake of Cr(III) was carried out using DGT devices containing the Chelex-100 resin (Chelex-100-DGT). A correlation coefficient of 0.993 was obtained for the linearity of the immersion curves (mass versus time) using DE81-DGT. The diffusion coefficient values for Cr(VI) through the agarose diffusive layer were equal to 4.89 +/- 0.5 x 10(-6) cm(2) s(-1) and 3.95 +/- 0.02 x 10(-6) cm(2) s(-1) (T=23 +/- 1 degrees C, I=0.03 mol L-1 NaNO3) were obtained by using diffusion cell and immersion curves, respectively. The retention of Cr(VI) by the DE81 membrane in a synthetic sample and river water was not affected by the pH over a wide range 4-9). Recoveries of Cr(VI) between 90% and 120% from solutions of ionic strength ranging from 0.01 to 0. 5 mol L-1 NaNO3 were achieved. Finally, the redox speciation analysis of Cr(III) and Cr(VI) in spiked river water and synthetic samples was performed with recoveries greater than 80% and 87% by using Chelex-100-DGT and DE81-DGT devices, respectively. Those results were in excellent agreement with the diphenylcarbazide spectrophotometric method. (c) 2016 Elsevier B.V. All rights reserved. (AU)

Processo FAPESP: 15/03397-4 - Especiação e fracionamento de metais (e alguns semi-metais) em água e solo
Beneficiário:Amauri Antonio Menegário
Modalidade de apoio: Auxílio à Pesquisa - Regular