Open AccessChromium Speciation Using Flow-injection Preconcentration on Xylenol Orange Functionalized Amberlite XAD-16 and Determination in Industrial Water Samples by Flame Atomic Absorption Spectrometry
Author(s) -
Reena Saxena,
Niharika Sharma,
Shelja Tiwari
Publication year - 2015
Publication title -
analytical sciences
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.392
H-Index - 73
eISSN - 1348-2246
pISSN - 0910-6340
DOI - 10.2116/analsci.31.1303
Subject(s) - chemistry , chromium , amberlite , detection limit , elution , solid phase extraction , xylenol orange , atomic absorption spectroscopy , chelating resin , chromatography , analytical chemistry (journal) , nuclear chemistry , ion , adsorption , metal ions in aqueous solution , physics , organic chemistry , quantum mechanics
A speciation method for Cr(III) and Cr(VI) by on-line solid-phase extraction using a flow-injection system with FAAS has been proposed. The Cr(III) was selectively retained at pH 5 on the AXAD16-XO chelating resin and was eluted using 0.5 mol L(-1) HNO3. The preconcentration factor and the detection limit (3σ) of 73 and 0.11 μg L(-1), respectively, were obtained for a 120-s preconcentration time. The precision (%RSD) at the 100 μg L(-1) level was 1.08%. The linearity for Cr(III) measurements was up to 600 μg L(-1). The total chromium was determined by reducing Cr(VI) to Cr(III) using hydroxylamine hydrochloride, and the Cr(VI) concentration was obtained by subtraction from the total chromium concentration. The effect of interfering ions was examined towards the selectivity of the proposed system for Cr(III). Spike recovery studies in industrial water samples were carried out using standard Cr(III) and Cr(VI) solutions traceable to NIST. The proposed method was validated using SRM 1643e (Trace Elements in Water) supplied by NIST, USA.