University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Website: @unf

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Classification: Metal -> copper

Citations 13

"Combined Generator/separator. 2. Stibine Generation Combined With Flow Injection For The Determination Of Antimony In Metal Samples By Atomic Emission Spectrometry"
Analyst 1992 Volume 117, Issue 10 Pages 1603-1608
Hengwu Chen, Ian D. Brindle and Shaoguang Zheng

Abstract: A modified hydride generator/gas - liquid separator was designed for the determination of Sb in metals by flow injection DC-plasma AES (cf. Ibid., 1992, 117, 407). Reduction of Sb(V) to Sb(III) was effected offline with cysteine, the presence of which also accelerates the BH4- reaction and reduces interference from transition metals and other hydride-forming elements (except Se). The calibration graph was rectilinear from 50 to 250 ng mL-1, and the detection limit was 7.5 ng mL-1 for a 0.5 mL sample. The coefficient of variation (n = 12) at 200 ng mL-1 was 0.9%. The method was applied to iron and copper. Application of a new continuous hydride generator to the determination of antimony in metals by flow injection is described. A modified hydride generator/gas-liq. separator has been designed. The detection limit for antimony is 7.5 ng mL-1 for a 0.5 mL sample. For solutions containing 200 ng mL-1 of antimony, the relative standard deviation is 0.9%. Reduction of antimony(V) to antimony(III) is effected by off-line prereduction with L-cysteine. L-Cysteine also accelerates the tetrahydroborate(III) reaction and reduces interferences from transition elements and, with the exception of selenium, other hydride-forming elements. Results are reported for the determination of antimony in iron and copper samples.
Antimony Spectrophotometry Interferences Phase separator Volatile generation Volatile generation

"L-Cysteine As A Reducing And Releasing Agent For The Determination Of Antimony And Arsenic Using Flow Injection Hydride-generation Atomic Absorption Spectrometry. 2. Interference Studies And The Analysis Of Copper And Steel"
Analyst 1993 Volume 118, Issue 11 Pages 1425-1432
Bernhard Welz and Marcella Sucmanová

Abstract: The method described in Part I (see abstract number 5D157) was used for the determination of Sb and As in Cu and steel. Cu was digested by cautious treatment with 7 and 14 M HNO3 and the digest was diluted with water and mixed with 10% L-cysteine solution Steel was heated with 10 M HCl followed by sequential treatment with 14 and 7 M HNO3, H2O2 and 7 and 14 M HNO3. The digest was evaporated to near-dryness and the peroxide-acid sequence was repeated 4 times at 135°C. The final residue was dissolved in 7 M HNO3 before the addition of 5% L-cysteine solution The resulting sample solution were diluted with water before analysis. Tolerance limits for Ni(II) and Cu(II) were 250 and 500 mg/l, respectively, in the determination of Sb. The corresponding limits in the determination of As were 200 mg/l and >1000 mg/l. However, if KI was used as reductant instead of L-cysteine, only 100 mg/l could be tolerated. In the analysis of standard reference materials, results agreed with certified values.
Antimony Arsenic Sample preparation Spectrophotometry Interferences Reference material

"Application Of 2-mercaptobenzothiazole-modified Silica Gel To Online Preconcentration And Separation Of Silver For Its Atomic Absorption Spectrometric Determination"
Analyst 1998 Volume 123, Issue 2 Pages 239-243
Qiaosheng Pu, Qiaoyu Sun, Zhide Hu and Zhixing Su

Abstract: 2-Mercaptobenzothiazole-modified silica gel was used for the flow injection online pre-concentration-separation and determination of silver by flame atomic absorption spectrometry. Two types of manifold, with one or two columns, were adopted. Silver ion was selectively adsorbed from 0.05 to 6 M HNO3 solution and was readily desorbed by thiourea solution The ions coexisting with Ag(I) exhibit virtually no interference in the determination with the exception of Cl-. An Ag(I) concentration ≥1 ppb could be determined reliably if a long pre-concentration time was used. The sample throughput was 60 h-1 using the two-column manifold with a pre-concentration time of 60 s. Ag in a geological sample, a copper metal sample and a lead nitrate sample was determined satisfactorily.
Silver Spectrophotometry Preconcentration Silica gel Interferences

"Determination Of Antimony By Continuous Hydride Generation Coupled With Nondispersive Atomic Fluorescence Detection"
J. Anal. At. Spectrom. 1995 Volume 10, Issue 11 Pages 969-974
Alessandro D'ulivo, Leonardo Lampugnani, Giovanna Pellegrini and Roberto Zamboni

Abstract: A sensitive method for the determination of Sb at ultratrace levels was developed by coupling continuous hydride generation with non-dispersive atomic fluorescence detection. A miniature argon-hydrogen diffusion flame was employed as the atomizer and a commercially available electrodeless discharge lamp as the light source, One of the main problems was the scattering signal generated by small droplets of solution which markedly deteriorated the signal-to-noise ratio. A simple way to remove the scattering signal was to operate under mild reaction conditions in order to minimize droplet formation. Under the optimized conditions, a limit of detection of 22 pg cm(-3) of Sb (3s of the blank) was achieved, with a precision of 1.2% at the 5 ng cm(-3) level and the calibration graphs were linear over more than 4 decades of concentration, L-Cysteine was employed both in the pre-reduction step and in the control of the interference effects arising from concomitant elements and acid mixtures, The analytical procedure was applied to the determination of Sb in certified reference materials of sediments, metallic copper and riverine water. (29 References)
Antimony Fluorescence Optimization Reference material Volatile generation Interferences Ultratrace Volatile generation

"Determination Of Arsenic In The Presence Of High Copper Concentrations Using Flow Injection Analysis - Hydride[-generation] Atomic Absorption Spectrometry"
Fresenius J. Anal. Chem. 1993 Volume 346, Issue 6-9 Pages 683-685
C. Schmidt and M. Bahadir

Abstract: Landfill waste water from polymer shredding waste of electrical cable (10 ml) was mixed with 5.5% hydroxylammonium chloride solution (1 ml) to reduce Cu(II) to Cu(I) and with 37% HCl (3 ml) and a KI-ascorbic acid reagent to reduce As(V) to As(III) and ppt. CuI and PbI2. After centrifugation, a 0.5 mL portion of the solution was injected into 4.35% HCl as carrier and the AsH3 generated with NaBH4 was determined by AAS. The solution contained 10 g/l of Cu(II), 0.15 g/l of Pb(II), 25 mg/l of Fe(III) and 0.4 g/l of Ni(II). Down to 1 µg/l of As could be detected in such solution
Arsenic Spectrophotometry Speciation Volatile generation Volatile generation

"Reversed-phase High Performance Liquid Chromatographic Separation Of Some Trace Impurities In Oxygen-free Electronic Copper By Post-column Chelation With 4-(2-pyridylazo)resorcinol And Arsenazo-III"
J. Chromatogr. A 1992 Volume 605, Issue 1 Pages 63-68
Rajananda Saraswati and T. H. Rao

Abstract: Cu samples were dissolved in HNO3, boiled, then diluted with water. The solution was subjected to electrolysis at 0.6 A with Pt electrodes to remove the Cu, heated, diluted with water, then portions were subjected to HPLC on a column (30 cm x 3.9 mm) of Spherisorb S-5 ODSI, with a mobile phase (1 mL min-1) of 1 mM octane-1-sulfonate - 0.023 M tartaric acid at pH 5.5 (for Mn, Fe, Co, Ni, Zn, Bi; Group A) or pH 6.0 (for Al, Cr, Zn, Pb; Group B). Post-column derivatization was carried out with 0.25 mM 4-(2-pyridylazo)resorcinol - 23 mM tartrate and detection at 533 nm for Group A metals; or with 1 mM 2,2'-arsenazo III - 0.3% NH3 solution and detection at 600 nm for Group B metals. Absolute detection limits ranged from 0.1 to 2.4 ng.
Manganese Iron Cobalt Nickel Bismuth Zinc Aluminum Chromium Lead HPLC Sample preparation Post-column derivatization Chelation

"Determination Of Trace Concentrations Of Bismuth By Inductively Coupled Plasma Atomic-emission Spectrometry With Hydride Generation"
Spectrochim. Acta B 1987 Volume 42, Issue 1-2 Pages 119-128
Taketoshi Nakahara, Kuniyuki Nakanishi and Tamotsu Wasa

Abstract: The continuous-flow hydride-generation apparatus used was as described previously (Anal. Chim. Acta, 1981, 131, 73; Appl. Spectrosc., 1983, 37, 539). The sample solution in 1 M HCl and 1% NaBH4 solution in 1% NaOH were pumped at 16 and 5.5 mL min-1, respectively, and the BiH3 evolved was carried to the ICP in a stream of Ar for the emission intensity at 223.06 nm to be measured. The instrumental coefficient of variation (n = 10) for 0.5, 2, 20 and 200 ng mL-1 of Bi were 3.5, 2.8, 2.2 and 1.3%, respectively, the limit of detection was 0.35 ng mL-1, and a graph of emission intensity vs. log. Bi concentration. was rectilinear for ~1 ng mL-1 to ~10 µg mL-1. The method of standard additions was used for actual determinations, in the presence of 0.1 M thiourea to minimize interference. Results for various geological reference standards, standard copper and standard aluminum alloys (digestion procedures described) agreed well with reported or certified values.
Bismuth Spectrophotometry Sample preparation Interferences Reference material Standard additions calibration Volatile generation Volatile generation

"Determination Of Trace Amounts Of Phosphorus In Copper After Preconcentration By Carrier Precipitation And Flotation"
Anal. Sci. 1994 Volume 10, Issue 4 Pages 669-670

Abstract: Cu wire was etched with acetic acid ultrasonically for 5 min, rinsed with water, dipped in acetone and dried in a vacuum desiccator. HCl and 31% H2O2 were added, the solution was boiled to remove excess peroxide, diluted with water and 5 mg/ml Al solution and aqueous 15 M ammonia were added to form flocculent hydrated aluminum oxide carrier precipitates and the ammine complex of Cu(II) at pH 8.5. Sodium oleate and sodium dodecylbenzenesulfonate in 70% ethanol were added and the solution was filtered. The foam was destroyed with 99.5% ethanol and the precipitate was washed with 6% ammonium chloride of pH 8.5 and dissolved in 1 M HCl. HBr (48%) was added to the filtrate and evaporated to dryness. The residue was dissolved in 1 M HNO3 and mixed with 1 M HNO3 containing 5% ascorbic acid or 5% ascorbic acid and Al. The solution was diluted with HNO3 and injected into the FIA system previously described (Ibid., 1994, 10, 389) to determine the phosphate content spectrophotometrically. A large excess of ascorbic acid was required to eliminate interference from Cu. The calibration graph was linear up to 20 µg of phosphate with a detection limit of 0.16 µg/g of P and recovery of >95%.
Phosphorus Spectrophotometry Sample preparation Interferences Preconcentration Precipitation

"Determination Of Selenium In Copper Metal Using Flow Injection Hydride-generation Atomic Absorption Spectrometry With Continuous-flow Matrix Isolation"
Anal. Proc. 1991 Volume 28, Issue 1 Pages 18-20
Stephen G. Offley, Nichola J. Seare, Julian F. Tyson and Helen A. B. Kibble

Abstract: Selenium could be determined in copper sample solution by hydride-generation AAS, after removal of Cu by passage through a micro-column of Dowex 50W-X8 (H+ form). Optimum flow rate was 2 mL min-1 and optimum pH was ~2.0. The system and method of analysis are described in detail. Results for two reference samples agreed with certified values. The limit of detection was 2.1 ng mL-1 of Se, the coefficient of variation was 1.5% (n = 12) at 10 ng mL-1, and the sample throughput was 17 h-1.
Selenium Spectrophotometry Column Reference material Matrix removal

"Applications Of Trace Metals Analysis At ICI Specialties Research Centre"
Anal. Proc. 1993 Volume 30, Issue 11 Pages 440-441
Sharon C. Stephen

Abstract: The determination is discussed of Cr(III) and Cr(VI) in dyes by LC on a column (25 cm x 4.6 mm) of Hypersil ODS with a mobile phase (2 ml/min) of tetrabutylammonium sulfate of pH 6.75/acetonitrile (4:1) with detection at 380 nm, by AAS at 357.9 nm and by dialysis followed by AAS or ICP-AES. Trace impurities in Cu were determined using ICP-MS with In as internal standard and FIA in a dilute HNO3 carrier stream with solvent extraction. Results were compared to certified values of reference materials. Results are tabulated for the determination of Ag, As, Bi, Fe, Pb and Sb.
Chromium(III) Chromium(VI) Silver Arsenic Bismuth Iron Lead Antimony Mass spectrometry Spectrophotometry Spectrophotometry Sample preparation Speciation Reference material Internal standard Dialysis

"Rapid Determination Of Copper In Various Copper Base Alloys By Flow Injection Analysis"
Bunseki Kagaku 1980 Volume 29, Issue 10 Pages T73-T78

Abstract: A flow injection method is described for the spectrophotometric determination of copper in various types of copper-base alloys. The system utilizes either the light absorption of aquacopper(II) ion at 805 nm or the light absorption of colored complex of copper(II) with EDTA (730 nm). Simple dissolution of alloys in nitric acid in the presence of tartaric acid suffices for sample preparation. The procedures have been applied to standard samples of copper-base alloys including several types of brasses, beryllium copper, deoxidized copper, German silver and aluminum bronze. The results obtained agree very satisfactorily with the certified values for these alloys. The precision is better than 0.5 % for the aquacopper(II) ion method. The sampling rate is 1 7 samples per hour.
Copper Spectrophotometry Method comparison Reference material

"Study On Applicability Of Trace Element Determination In Solution With High Salt Concentration By FIA-flame AAS"
Fenxi Shiyanshi 1993 Volume 12, Issue 4 Pages 19-22
Yuan, Y.;Guo, X.W.

Abstract: A pre-concentration system (schematic diagram given) was developed for flame AAS and applied to the determination of Pb in Cu metal, and Ag and Cd in geological samples. For determination of Ag and Cd in ore, sample (2 g) was digested with 10 mL of 1:1 aqua regia by heating, the solution was evaporated to ~5 ml, mixed with 0.5 mL of 1% gelatin before dilution with water to 10 mL. The solution was analyzed by the cited method with 1% aqua regia as carrier stream. The detection limits were 0.02 µg/g of Ag and 0.01 µg/g of Cd; RSD (n = 23) were 0.5%.
Lead Silver Cadmium Spectrophotometry Preconcentration

"Simultaneous Determination Of Trace Arsenic, Antimony And Bismuth In Electrolytic Copper Sample By Flow Injection Hydride Generation Coupled With Inductively Coupled Plasma Atomic Emission Spectrometry"
Fenxi Shiyanshi 1998 Volume 17, Issue 1 Pages 57-59
Yu, X.;Chen, J.;Wang, S.;Liao, Z.;Jiang, Z.

Abstract: The technique of flow injection hydride generation coupled with ICP-AES and its application on determining trace As, Sb and Bi in electrolytic Cu was studied. An effective method was established, the relative standard deviation for determination of As, Sb, Bi was 2.3, 1.8, 2.8% (n = 11), and the detection limit was 0.3, 0.3, 1.15 µg/g respectively.
Arsenic Antimony Bismuth Spectrophotometry Simultaneous analysis Volatile generation