Furnace Atomic Absorption Spectrometric Determination Research Articles

Graphite Furnace Atomic Absorption Spectrometric Determination of Iron, Cobalt, Nickel, and Copper at Parts-Per-Billion Level in High-Purity Lanthanum Fluoride

This paper describes an analytical method for the quantitation of iron, cobalt, nickel, and copper in lanthanum fluoride at trace levels with graphite furnace atomic absorption spectrometry (GFAAS) without using any matrix modifier. These metals were preconcentrated in HNO3 and analyzed directly. The detection limits for iron, cobalt, nickel, and copper were found to be 3, 1, 2, and 2 ppb, respectively. The average precision of measurements (°/o RSD) for all the elements was <10%.

Direct graphite furnace atomic absorption spectrometric determination of metals in sea water: application of palladium modifiers and a fractal approach to their analytical support

Sea water, like other high-salinity matrices, causes severe interferences in the direct determination of metals by graphite furnace atomic absorption spectrometry (GFAAS), even when Zeeman-effect background corrections is applied. A method for eliminating these interferences by the application of mixed modifier system of ammonium oxalate and tetraamminepalladium(II) chloride is presented. In particular these modifiers optimize the direct GFAAS determination of lead and manganese. For cadmium, however, only ammonium oxalate should be used as a modifier. The geometry of the microdistribution of palladium on the palladium-conditioned graphite platform was investigated in order to elucidate possible stabilizing effects of palladium on the analytes which were observed with the different modifiers. Fractal characteristics of the palladium elemental distribution were ascertained by a scanning electron microscope-energy-dispersive x-ray spectrometer image box-counting analysis. The fractal dimension [ D B(0) = 1.77 ± 0.04 and 1.81 ± 0.04] and electron microscopic investigations indicated differences in the structure of palladium deposits on the platform. These variations in the palladium geometry affect the analytes to a certain extent.

Determination of gallium in iron meteorites and other iron-rich materials by graphite furnace atomic absorption spectrometry

A procedure was developed for the graphite furnace atomic absorption spectrometric determination of gallium in high-iron geological materials such as iron meteorites. To overcome sevre interference from iron, gallium is extracted as a chloro complex from 5 M hydrochloric acid into isobutyl methyl ketone. Iron is reduced by addition of potassium iodide and its co-extraction into the organic phase is thereby decreased to <2%. As determined by analysis of geological reference materials, the limit of detection (3σ) was about 0.05 μg g t-1. The precision (R.S.D.) ranged from 0.8 to 1.1%. The accuracy, as determined from the relative error, ranged from 0.07 to 7.7% for the three standards analysed. In solutions containing 1 μg g −1 gallium, no interferences were observed for up to 1500 μg ml −1 nickel, 1200 μg ml −1 copper, 200 μg ml −1 cobalt, 100 μg ml −1 arsenic and 200 μg ml −1 germanium. The method was applied to the analysis of eight iron meteorites that had been previously analysed by neutron activation analysis. The mean relative deviation of 8.6% was satisfactory.

The Effect of Metal Chlorides, Sulfates and Nitrates on Atomization of Selenium in Graphite Furnace Atomic Absorption Spectrometry

The effects of various single and mixed metal chloride, sulfate, and nitrate upon the graphite furnace atomic absorption spectrometric determination of Se in aqueous solutions were studied. The results for some chlorides were compared with those for sulfate and nitrate. Among the metals studied (Pd, Hg, Cd, Ni, Cu, Mg, Ag) the best enhancement in the Se atomic absorption signal was obtained by the mixing pair Hg-Pd chloride.

Platform in furnace Zeeman-effect atomic absorption spectrometric determination of arsenic in beer by atomization of slurries of sample ash

A precise and accurate procedure is proposed for the determination of As in beer samples at the ng g–1 level by electrothermal atomic absorption spectrometry. The sensitivity of this technique is enhanced by a factor of 2.5 by introducing a preconcentration step, consisting of preliminary dry ashing of the samples and direct injection into the L'vov platform of a slurry of the ashes. The high background caused by the beer sample matrix is compensated for by the use of Zeeman correction. The arsenic is atomized under stabilized temperature platform furnace conditions with the addition of a nickel–ascorbic acid chemical modifier. The effect that each of these compounds has on the determination of As was studied, both separately and in combination. The methodology developed has a characteristic mass of 35 pg, which corresponds to a concentration of 0.7 ng of As per g of beer, a recovery of 102 ± 2% and a relative standard deviation of 4.5% for six independent analyses of a sample containing 8.5 ng g–1 of As. The accuracy of the method was confirmed by the analysis of a certified reference material sample. The proposed procedure was used to analyse real samples of beer and the results are comparable to those found by hydride generation atomic absorption spectrometry.

PALLADIUM-INDUCED ANALYTE ISOFORMATION EFFECTS ON LEAD AND VANADIUM IN THE GRAPHITE FURNACE

The graphite furnace atomic absorption spectrometric (GFAAS) determination of lead and vanadium in medical and environmental materials was accomplished by using palladium as the analyte isoformer. Citric acid promoted the formation of active deposits of carbon in the graphite tube. Pd demonstrated to be equally useful for te GFAAS evaluation of volatile as well as refractory metals

Graphite Furnace Atomic Absorption Spectrometric Determination of Ultra-Trace Levels of Cobalt after Solvent Extraction Using W/O/W Emulsions as Liquid Surfactant Membranes

A high-enrichment method by liquid-liquid extraction using liquid surfactant membranes was developed for the determination of cobalt at pg cm-3 levels by graphite furnace atomic absorption spectrometry (GF-AAS). Two cubic centimeters of w/o [water in oil, in this case dilute hydrochloric acid in kerosene (1:1) containing 2-ethylhexyl hydrogen 2-ethylhexylphosphonate (PC-88A)] emulsion droplets coated with sorbitan monooleate are dispersed in a resulting volume of 1000 cm3 of an aqueous sample solution (pH 4.7-5.8) containing less than 1 mg of cobalt(II). The analyte is extracted into the organic phase to form a complex with PC-88A and successively back-extracted into the inner acidic aqueous phase. After the w/o emulsion phase is separated from the outer aqueous phase, the emulsions are demulsified into the organic and inner aqueous phases. The cobalt content is then determined by GF-AAS with an injection volume of 10 mm3 of the inner aqueous phase. By this procedure, a concentration factor of 550 was achieved for cobalt(II). As a result, the detection limit of cobalt was 10pgcm3, and the calibration graph was linear up to 1 mg cm-3 of cobalt(II). The relative standard deviation for ten replicate measurements of 50 pg cm-3 cobalt(II) was 7.1%. The results of an analysis of simulated nuclear reactor coolant water are given.

Graphite Furnace Atomic Absorption Spectrometric Determination of Bismuth(III) after Coprecipitation with Hafnium Hydroxide

Abstract A method for the coprecipitation of bismuth(III) with hafnium hydroxide followed by a graphite-furnace atomic absorption spectrometric determination is described. Hafnium hydroxide coprecipitates quantitatively 0.05–3 μg of bismuth(III) from 50–400 cm3 of sample solution at pH 5.8–11.2. The presence of 2.5–50 mg of hafnium in 25 cm3 does not affect the atomic absorbance of bismuth(III). The calibration curve is linear for 0.05–3 μg of bismuth(III) in 25 cm3 and passes through the origin. Interference from the presence of large amounts of silver can be eliminated by removing silver as the ammine complex produced by the coprecipitation procedure at above pH 11 with aqueous ammonia. Several other matrix ions investigated do not interfere with the determination in at least a 500-fold mass ratio to bismuth(III). This method was successfully applied to the determination of trace bismuth(III) in commercial metal silver (purity: 99.99%), and is also applicable to the determination of trace amounts of bismuth(III) in water sample.

Graphite furnace atomic absorption spectrometric determination of iridium, rhodium and ruthenium in high-purity platinum after matrix extraction

Ir, Rh and Ru are separated from a large excess of platinum by extraction with isoamyl alcohol-isobutyl methyl ketone mixture. Graphite furnace atomic absorption spectrometry using the method of standard addition is then used to determine the metals with satisfactory precision and accuracy.

Graphite furnace atomic absorption spectrometric determination of chromium, nickel, cobalt, molybdenum, and manganese in tissues containing particles of a cobalt-chrome alloy

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTGraphite furnace atomic absorption spectrometric determination of chromium, nickel, cobalt, molybdenum, and manganese in tissues containing particles of a cobalt-chrome alloyFoster. Betts and Alicia. YauCite this: Anal. Chem. 1989, 61, 11, 1235–1238Publication Date (Print):June 1, 1989Publication History Published online1 May 2002Published inissue 1 June 1989https://doi.org/10.1021/ac00186a012RIGHTS & PERMISSIONSArticle Views110Altmetric-Citations10LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (564 KB) Get e-Alerts Get e-Alerts

Graphite furnace atomic absorption spectrometric determination of nickel at sub-ng g–1levels in marine samples by carbonyl generation with in situ pre-concentration

Reduction of NiII in solution by addition of BH4– and its carbonylation in a stream of CO-Ar serves to transfer the volatile Ni(CO)4 from a generation cell to a pre-heated graphite furnace where it undergoes decomposition and deposition at T > 500 °C. Subsequent atomisation at T > 2700 K and measurement of the atomic absorption serves to quantify Ni in test samples by direct comparison with signals derived from identically treated solutions of standards. The system is ca. 80% efficient and is characterised by a concentration detection limit (3σ) of 4 ng l–1, based on a 10-ml test sample. Results are presented for the analyses of several natural water and biological reference materials.

Uphill Transport Driven by Hydrolysis of a Complex Partitioned into a Liquid Membrane: Application to the Preconcentration of Arsenic

Abstract AsI3 is demonstrated to partition from a 9 M HC1, 0.10 M KI, 0.10 H ascorbic acid solution into kerosene and dodecane membranes which do not contain complexing agents. Subsequent hydrolysis at the membrane receiver interface causes a transport of As against its concentration gradient. A 60 minute experiment with a 4 mL receiver solution and a 200 mL sample permits the preconcentration of As by a factor of 16 ± 0.5. The interferences of aluminum and phosphate on the graphite furnace atomic absorption spectro-metric determination of As are eliminated. This transport mechanism, which has not been previously reported, may allow the range of species which can be preconcentrated by transport across supported liquid membranes to be significantly extended.

Graphite furnace atomic absorption spectrometric determination of selenium in plant materials following combustion in a stream of oxygen

The determination of selenium in plant materials by graphite furnace atomic absorption spectrometry can be difficult not only because of the low levels of the element found in non-accumulating species, but because the technique is particularly prone to interferences from the sample matrix. The amelioration of these problems by the use of a commercially available combustion system in which the sample is burned in a stream of oxygen and the volatilised Se collected in a small volume of 2 M acetic acid containing hydrogen peroxide has been investigated. The performance of this system in combination with determination by atomic absorption spectrometry, using electrothermal atomisation with totally pyrolytic graphite furnace tubes and platforms, and copper as a matrix modifier, has been assessed. The results obtained from the analysis of three standard reference materials and nine herbage samples are presented. The limit of determination of the method is 3 ng g–1 Se on a dry mass basis.

Pyrolytic carbon coating method for contoured graphite tubes and their use in furnace atomic absorption spectrometric determination of boron and uranium

Tubes are machined from rods of suitable graphite according to a modified design so that there is a recess of 20-μl capacity in the inner surface at the tube centre; this improves reproducibility and sensitivity. Pyrolytic carbon coating is accomplished independently of the atomic absorption instrument by using a simple apparatus (dimensions are given). Tube lifetimes are considerably longer than those of both coated and uncoated commercial tubes. The coated tubes described have lifetimes long anough at high atomizing temperatures to determine uranium and boron on a routine basis. The boron memory is eliminated and that of uranium successfully controlled. The addition of organic solvents to the analyte solution to enhance sensitivity for uranium is reported.

Oxygen ashing and matrix modifiers in graphite furnace atomic absorption spectrometric determination of lead in whole blood.

Oxygen ashing and matrix modifiers in graphite furnace atomic absorption spectrometric determination of lead in whole blood.

Reduction of matrix effects with a soluble organic acid in the carbon furnace atomic absorption spectrometric determination of cobalt, copper, and manganese in sea water

Reduction of matrix effects with a soluble organic acid in the carbon furnace atomic absorption spectrometric determination of cobalt, copper, and manganese in sea water