Please use this identifier to cite or link to this item:
Type: Artigo de periódico
Title: Silica modified with zirconium oxide for on-line determination of inorganic arsenic using a hydride generation-atomic absorption system
Author: Macarovscha, GT
Bortoleto, GG
Cadore, S
Abstract: In the present work, an on-line pre-concentration system, using SiO2/ZrO2 as solid phase adsorbent, for the determination of low concentrations of arsenic was developed. In this procedure, total inorganic arsenic present in the sample is reduced to As (111) with L-Cysteine and the solution is passed into a glass column (phi(i) = 3 mm; h = 35 mm) containing 70 mg of SiO2/ZrO2 (100-230 mesh) to retain the As (III), with the solution flowing at 3.2 mL min(-1). After 2 min, the concentrated species are eluted with 3 mol L-1 HCl (3.2 mL min(-1)) loading a 150 mu L loop while a 1.0% (m/v) sodium borohydride solution loads the other loop of a FI-HG AAS system. The elution step is carried out during 7 s and, at the same time, the SiO2/ZrO2 phase is regenerated for the next concentration cycle. The arsine generated is carried with N-2 (flow rate = 90 mL min(-1)) to a quartz cell where the electrothermal atomization process occurs. Under these conditions, a 20-fold enrichment factor is obtained considering the increase of sensitivity in the analytical curve after the concentration step. The limits of detection and quantification were 0.05 and 0.35 mu g L-1, respectively, with an injection frequency of about 28 h(-1) and relative standard deviation lower than 8%. Four metallurgical reference materials were analyzed with the proposed method after their acid dissolution. The results obtained were in good agreement with certified values. (c) 2006 Elsevier B.V. All rights reserved.
Subject: arsenic
liquid-solid extraction
zirconium oxide
Country: Holanda
Editor: Elsevier Science Bv
Rights: fechado
Identifier DOI: 10.1016/j.talanta.2006.06.006
Date Issue: 2007
Appears in Collections:Unicamp - Artigos e Outros Documentos

Files in This Item:
File Description SizeFormat 
WOS000244536800023.pdf353.93 kBAdobe PDFView/Open

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.