Hydride generation-pervaporation-atomic fluorescence detection prior to speciation analysis of arsenic in dirty samples

Abstract

A flow injection-pervaporation method for the continuous derivatisation and determination by atomic fluorescence spectrometry is proposed for the first time in order to speciate As as As III and As V . The sample at different pHs was injected into a 6 M HCl stream and then mixed with 0.5% or 0.05% m/v NaBH 4 . The reactant mixture was transported to the lower chamber of a pervaporator from which the arsine generated evaporated to the air gap between the liquid and the membrane, diffused through the latter and was swept out of the acceptor chamber by a hydrogen-argon stream into the chemically generated hydrogen diffusion flame. An auxiliary H 2 flow was necessary to support the flame. The linear ranges of the calibration curves for As III and As V were from pg ml 21 to ng ml 21 , with correlation coefficients, r 2 , better than 0.99. For As III , the reproducibility and repeatability, expressed as relative standard deviation, were 3.0% and 1.1%, respectively, and for As V were 3.2% and 1.3%, respectively. The detection and quantification limits were 0.42 ng ml 21 and 0.61 ng ml 21 for As III and AS V , respectively. The method thus developed was applied to 'dirty' aqueous samples with solid particles in suspension, without prior filtration, and provided a sampling frequency of 12 h 21 . Experimental ApparatusAn Excalibur PSA 10033 non-dispersive atomic fluorescence detector (PS Analytical, Orpington, UK) fitted with a monoelemental boosted discharge hollow cathode lamp (primary current 27.5 mA, boosted current 35.0 mA, Victoria, Australia) for As, as the excitation source, a hydrogen diffusion flame, as the atom cell, and a specific filter to achieve isolation and reduction of flame emission in conjunction with a solar blind

Automatic determination of arsenate in drinking water by flow analysis with dual membrane-based separation

“…The newly developed FA method provides better sensitivity for the determination of As(V) than other spectrophotometric FA methods (e.g., 51 g L -1 (Boonjob, Miró, & Kolev, 2013) and 21 g L -1 (Y. Zhang, Miró, & Kolev, 2015)) and sensitivity comparable to that provided by FA methods utilizing bulky and expensive atomic optical detectors (e.g., atomic fluorescence detector -0.61 g L -1 (Caballo-Lopez & Luque de Castro, 2002) and atomic absorption detector -0.5 g L -1 (Y. Zhang & Adeloju, 2008).…”

Potential of the hydride generation technique coupled to inductively coupled plasma optical emission spectrometry for non-chromatographic As speciation

“…Suitability of the most commonly employed pre-reducing agents for As, i.e. KI 10,11,13,14,17,18,26,28,[30][31][32][33][34][35]38,[40][41][42] and TU, 13,16,36,37 alone or combined with AA, as well as the less frequently chosen LC 20,28,29,36,39 was tested for this aim. All the experiments were conducted at a xed NaBH 4 concentration (1.0%) and variable HCl concentrations in the S and A solutions.…”

“…Hence, most of the studies dealing with nonchromatographic As speciation by HG focus on i-As, and concern discrimination between As(III) and As(V) only. [21][22][23][33][34][35][36][37][38][39][40][41][42] In contrast, the role of o-As is rather diminished. Contribution of o-As to the quantied concentration of i-As or As(III) can only be assessed by evaluating the interferences of DMA and MMA on the As signal under the selected HG reaction conditions.…”

Analytical methods for sensing of health-hazardous arsenic from biotic and abiotic natural resources

“…The FIP-AFS assembly has been proved to a versatile, reproducible and rapid method for continuous speciation analysis of arsenic in 'dirty' aqueous samples. 127 A wide range of arsenic contaminated samples have been studied using HPLC-HG-AFS technique. The technique has applications in various elds for instance pore water, chromate-copper-treated wood leachates, wastewater, gold mine tailings, acid mine drainage or beer.…”