Please use this identifier to cite or link to this item:
Title: Surface arsenic speciation of a drinking-water treatment residual using X-ray absorption spectroscopy
Authors: Sarkar, Dibyendu 
Parsons, Jason G. 
Datta, Rupali K. 
Gardea-Torresdey, Jorge Luis 
Makris, Konstantinos C. 
Keywords: Residuals
Drinking water
Arsenic (As)
Issue Date: Jul-2007
Publisher: Elsevier B.V.
Source: Journal of Colloid and Interface Science, 2007, Volume 311, Issue 2, Pages 544–550
Abstract: Drinking-water treatment residuals (WTRs) present a low-cost geosorbent for As-contaminated waters and soils. Previous work has demonstrated the high affinity of WTRs for As, but data pertaining to the stability of sorbed As is missing. Sorption/desorption and X-ray absorption spectroscopy (XAS), both XANES (X-ray absorption near edge structure) and EXAFS (extended X-ray absorption fine structure) studies, were combined to determine the stability of As sorbed by an Fe-based WTR. Arsenic(V) and As(III) sorption kinetics were biphasic in nature, sorbing >90% of the initial added As (15,000 mg kg−1) after 48 h of reaction. Subsequent desorption experiments with a high P load (7500 mg kg−1) showed negligible As desorption for both As species, approximately <3.5% of sorbed As; the small amount of desorbed As was attributed to the abundance of sorption sites. XANES data showed that sorption kinetics for either As(III) or As(V) initially added to solution had no effect on the sorbed As oxidation state. EXAFS spectroscopy suggested that As added either as As(III) or as As(V) formed inner-sphere mononuclear, bidentate complexes, suggesting the stability of the sorbed As, which was further corroborated by the minimum As desorption from the Fe-WTR.
ISSN: 0021-9797
DOI: 10.1016/j.jcis.2007.02.078
Rights: © Elsevier Inc.
Appears in Collections:Άρθρα/Articles

Show full item record

Citations 10

checked on Jan 20, 2017

Citations 10

checked on May 24, 2017

Page view(s)

Last Week
Last month
checked on May 27, 2017

Google ScholarTM



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