Extraction of arsenate and arsenite species from soils and sediments

Abstract

The primary objective of this study was to develop a simple method that can be used to extract the more readily mobilizable and bioavailable arsenic species from soil and sediment while at the same time minimizing the transformation between (As III ) and (As V ), the two most commonly found arsenic species in the environment. Several extraction strategies were evaluated using phosphate as extractant in combination with either ethylenediaminetetraacetic acid (EDTA), hydroxylamine hydrochloride (NH 2 OH·HCl), or sodium diethyldithiocarbamate trihydrate (NaDDC).The addition of EDTA in the phosphate solution did not prevent As III from oxidation. While promising results were shown when 1% NH 2 OH·HCl was added, conversion of As III began to occur with extended extraction time (>12 h). Good results were achieved using 10 mM phosphate and 0.5% NaDDC where As III oxidation was clearly minimized. The combined phosphate and NaDDC solution was applied to several soil and sediment samples. As III spiked was quantitatively recovered in all soil types tested.

Mobility of arsenic and its compounds in soil and soil solution: The effect of soil pretreatment and extraction methods

“…In principle the abundance of individual arsenic compounds reflected these in soil extracts (Tables 2 and 3) but the data were quite varied and the assessment of the data is limited. Stability of arsenic compounds as well as macronutrient cations, anions and soluble organic carbon concentrations in soil solution should be discussed in this context [21,53]. Fig.…”

Dissolution of arsenopyrite (FeAsS) and galena (PbS) in the presence of desferrioxamine-B at pH 5

“…Speciation of As, namely As(III) and As(V), was conducted using an HPLC-AAS method described elsewhere (Georgiadis et al, 2006). Briefly, separation of As(III) and As(V) was conducted using an HPLC (Solvent Delivery System 9012, Varian, CA, USA) with a 100-lL injection loop for sample introduction.…”

Hydrogeochemistry of Groundwater and Arsenic Adsorption Characteristics of Subsurface Sediments in an Alluvial Plain, SW Taiwan

“…The As speciation analyses were determined using the method by Georiadis [17]. A mild extraction media of phosphate solution [18] and sodium diethyldithiocarbamate trihydrate (NaDDC) were used as extractants.…”