Co-precipitative pre-concentration with sodium diethyldithiocarbamate and ICP-AES determination of Se, Cu, Pb, Zn, Fe, Co, Ni, Mn, Cr and Cd in water

Sodium diethyldithiocarbamate in the presence of a weak oxidizing agent is used as a co-precipitative agent for the pre-concentration of Se, Cu, Pb, Zn, Fe, Co, Ni, Mn, Cr and Cd. A procedure was developed for ICP-AES determination of these elements after pre-concentration in river and waste water (an enrichment factor of 40). The recovery of all the elements tested for was more than 98%. The limits of determination (mg l⁻¹) (10 S.D. blank) are 0.001 (Cu, Co, Cr, Mn), 0.0007 (Zn, Cd), 0.003 (Se), 0.004 (Fe), 0.007 (Ni), and 0.01 (Pb).     

Chemical separation and electrothermal atomic-absorption spectrophotometric determination of Cd, Co, Cu and Ni in high-purity uranium

Summary An electrothermal atomic-absorption spectrophotometric method has been developed for the estimation of trace concentrations of Cd, Co, Cu and Ni in high-purity uranium after their chemical separation. The trace constituents from 100 mg of uranium sample in 3 M nitric acid solution were separated using 0.2 M di-n-octyl sulphoxide in xylene. The concentration of the analytes in the aqueous phase was determined by graphite furnace AAS. The detection limits were 0.001, 0.01, 0.025 and 0.05 ng for Cd, Co, Cu and Ni, respectively. The precision of the determinations was 7–14%. The effect on absorbances of the analytes due to the presence of Al, Ca, Fe, Mg, Pb, W and uranium was examined.

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Chemische Abtrennung und elektrothermische AAS-Bestimmung von Cd, Co, Cu und Ni in hochreinem Uran

Zusammenfassung Die Spuren werden aus einer 100 mg Uranprobe in 3 M salpetersaurer Lösung durch Extraktion des U mit Hilfe von 0.2 M Di-n-octylsulfoxid im Xylol abgetrennt und werden anschließend in der wäßrigen Phase durch Graphitofen-AAS bestimmt. Die Nachweisgrenzen betragen 0,001 ng (Cd), 0,01 ng (Co), 0,025 ng (Cu) und 0,05 ng (Ni). Die Reproduzierbarkeit beträgt 7–14%. Der Einfluß von Al, Ca, Fe, Mg, Pb, W sowie Resturan auf die Absorption der analysierten Elemente wurde untersucht.

     

Improved detection of transition and rare earth elements in marine samples with the CETAC DSX-100 preconcentration/matrix elimination system and ICP-MS

A new method for detection of trace metals in saline samples is described using batch preconcentration with subsequent ICP-MS analyses after direct sample insertion of the analyte loaded chelating resin. The samples were prepared using a CETAC DSX-100 system, which preconcentrates analytes and removes matrix components by a suspended particulate reagent (SPR). The SPR is consisting of polymeric beads of 0.2 μm size that selectively binds the trace metals by iminodiacetic chelating groups. The beads with bound analytes are then nebulized directly into the ICP-MS. The enrichment factors lay between 40 and 48 due to the enrichment of 120 mL suspension to 2.5–3.0 mL eluate. The method was applied and validated to the successful determination of traces of the transition metals Mn, Fe, Ni, Co, Cu, Zn, Cd, and Pb in the Open Ocean Seawater certified reference material NASS-4 and the Coastal Seawater certified reference material CASS-3. In addition to the certified constituents the rare earth elements La, Ce, Eu, Gd, Yb, and Lu were determined. Received: 15 Oktober 1999 / Revised: 1 February 2000 / Accepted: 3 February 2000     

Flow Analysis of Transition Metals by Thermal Lensing

The conditions for the flow determination of Al(III), Bi(III), Cd(II), Co(II), Cr(III), Cu(II), Fe(III), Mn(II), Nd(III), Ni(II), Pb(II), Pr(III), and Zn(II) by reaction with Xylenol Orange in aqueous solutions at pH 4.5 and the determination of Cd(II), Co(II), Cu(II), Fe(II), Ni(II), Pb(II), and Zn(II) by reaction with 4-(2-thiazolylazo)resorcinol in water–ethanol mixtures (5 : 1) at pH 5.0 using an injected sample volume of 80 L were proposed. The limits of detection were n × 10^–8–n × 10^–7 mol/L; the linearity ranges in the calibration graphs were of about three orders of magnitude; the relative standard deviation was of 3–7%.     

Improved detection of transition and rare earth elements in marine samples with the CETAC DSX-100 preconcentration/matrix elimination system and ICP-MS

A new method for detection of trace metals in saline samples is described using batch preconcentration with subsequent ICP-MS analyses after direct sample insertion of the analyte loaded chelating resin. The samples were prepared using a CETAC DSX-100 system, which preconcentrates analytes and removes matrix components by a suspended particulate reagent (SPR). The SPR is consisting of polymeric beads of 0.2 μm size that selectively binds the trace metals by iminodiacetic chelating groups. The beads with bound analytes are then nebulized directly into the ICP-MS. The enrichment factors lay between 40 and 48 due to the enrichment of 120 mL suspension to 2.5–3.0 mL eluate. The method was applied and validated to the successful determination of traces of the transition metals Mn, Fe, Ni, Co, Cu, Zn, Cd, and Pb in the Open Ocean Seawater certified reference material NASS-4 and the Coastal Seawater certified reference material CASS-3. In addition to the certified constituents the rare earth elements La, Ce, Eu, Gd, Yb, and Lu were determined. Received: 15 Oktober 1999 / Revised: 1 February 2000 / Accepted: 3 February 2000     

Verfahren zur Trennung und Anreicherung bei der Atomabsorptionsspektrometrie von Spurenverunreinigungen in schwerl?slichen Bleiverbindungen

Zusammenfassung Ein Trenn- und Anreicherungsverfahren zur AAS-Spurenanalyse in PbCl₂ und PbSO₄ wird beschrieben. Die Analysenproben werden im festen Zustand in einen Pb(DDTC)₂-Niederschlag umgewandelt. Die dabei gebildeten Dithiocarbamatkomplexe von Fe, Cu, Co, Ni, Cd, Zn werden durch Dreiphasenextraktion in MIBK konzentriert und mittels Flammen-AAS analysiert. Die Methode erlaubt die Bestimmung von 0,3 g/g Fe, 0,2 g/g Co, Ni und 0,05 g/g Cu, Cd, Zn mit einer relativen Standardabweichung von 0,5 bis 5%.

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Method for the separation and concentration of trace elements in the atomic absorption spectrometric analysis of insoluble lead compounds

Summary A method for the separation and concentration of trace elements in the analysis of PbCl₂ and PbSO₄ is described. The solid samples are transformed to Pb (DDTC)₂. The DDTC-complexes of Fe, Cu, Co, Ni, Cd, Zn thus formed are concentrated using three-phase extraction with MIBK and determined by flame AAS. The detection limit amounts to 0.3 gmg/g Fe, 0.2 g/g Co, Ni and 0.05 g/g Cu, Cd, Zn with a relative standard deviation of 0.5–5%.

     

Determination of Cd, Co, Cr, Cu, Fe, Mn, Ni and Pb in natural waters, alkali and alkaline earth salts by electrothermal atomic absorption spectrometry after preconcentration by column solid phase extraction

Methods are described for the determination of trace and ultra trace amounts of Cd, Co, Cr, Cu, Fe, Mn, Ni and Pb in natural waters, alkali and alkaline earth salts. Separation and preconcentration of trace metals is achieved by a column solid phase extraction procedure using silica gel modified with derivatives of dithiocarbamates — Na-DDTC (sodium diethyldithio-carbamate and HMDTC (ammonium hexamethylene-dithiocarbamate) as column packing material. The influence of the sorbent preparation procedure on the degree of sorption of the trace analytes is examined for different pH values of the sample solution. Isobutylmethyl ketone (IBMK) is proposed as an effective eluent for quantitative elution of retained metal ions. Optimal instrumental parameters for ETAAS determination of preconcentrated elements in organic eluate are presented. Practical application of sorbents in analysis of natural waters and alkali and alkaline earth salts is demonstrated. Proposed preconcentration procedure combined with ETAAS determination of trace analytes allows the determination of 0.04 g l^–1 Cd, 0.1 g l^–1 Cr, Cu, and Mn and 0.3 g l^–1 Co, Fe, Ni and Pb in natural waters and 1.10^–7% Cd, 3.10^–7% Cr and Mn, 7.10^–7% Co, Ni and Pb and 2.10^–6% Cu and Fe in alkali and alkaline earth salts.     

Bestimmung von Spurenelementen in Flu?wasser mit Hilfe der Voltammetrie

Zusammenfassung Bei der Bestimmung von Spurenelementen in Flußwasser durch Voltammetrie treten Störungen auf, die überwiegend von organischen Verunreinigungen verursacht werden. Die Einflüsse dieser Verunreinigungen können durch oxidative UV-Photolyse beseitigt werden.Im Anschluß an die Bestrahlung der Proben konnten in filtriertem Rheinwasser Zn, Cd, Pb, Cu, Ni, Co, Tl und mit Einschränkungen auch Mn voltammetrisch bestimmt werden. Die Konzentrationen an Bi und Se lagen unterhalb der Nachweisgrenze. Die Nachweisgrenzen für die genannten Elemente in Flußwasser bewegten sich in der Größenordnung zwischen 0,1 und 1 g/l. Vergleichsbestimmungen mit Hilfe der flammenlosen AAS (Graphitrohrküvette) ergaben gute Übereinstimmung für die Elemente Cu, Zn und Mn, während die Konzentrationen der anderen Elemente unterhalb der Nachweisgrenze der AAS lagen.Die Komplexierungskapazität des Rheinwassers für Zn, Cd, Pb und Cu wurde durch voltammetrische Titration ermittelt. Sie lag zwischen 5,0 und 0,7 g/l und nahm in der Reihenfolge Cu > Zn > Pb > Cd ab.

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Determination of trace elements in river water by means of voltammetry

Summary The determination of trace elements in river water by voltammetry is disturbed by the presence of organic substances. The influence of these substances can be eliminated by oxidative UV-photolysis.After UV irradiation the following elements were determined in Rhine water by voltammetry: Zn, Cd, Pb, Cu, Ni, Co, Tl and — with reservations — Mn. The concentrations of Bi and Se were below the detection limits. The detection limits in river water for the elements mentioned were determined and found to be between 0.1 and 1 g/l. Comparative determinations by AAS (graphite tube) showed good agreement for Cu, Zn and Mn, whereas the concentrations of the other elements were below the detection limits of AAS.The complexing capacity of Rhine water for Zn, Cd, Pb and Cu was determined by voltammetric titration. It decreased in the order Cu > Zn > Pb > Cd and was between 5.0 and 0.7 g/l.

     

Senio river ecosystem: characterization and distribution of inorganic species in water and sediments

Analytical results are reported for the determination of inorganic species in water and sediments sampled in the Senio river ecosystem. The species determined are Cu, Pb, Cd, Zn, Co, Cr, Ni, Fe, Mn, Hg, F-, Cl-, Br, NO3-, SO4-, Na+, K+, Ca++, Mg++, NH4+ in integrated water, and Cu, Pb, Cd, Zn, Co, Cr, Ni, Fe, Mn, Hg in sediments. For all the elements, in addition to detection limits, precision and accuracy are given: the former, expressed as relative standard deviation (sr), and the latter, expressed as relative error (e), were good, being in all cases lower than 6%. Limitedly to Cu, Pb, Cd and Zn a critical comparison with voltammetric measurements is also discussed.     

Determination of Cu,Cd, Ni,Pb and Zn in Edible Oils Using Reversed-Phase Ultrasonic Assisted Liquid–Liquid Microextraction and Flame Atomic Absorption Spectrometry

A simple and green reversed-phase ultrasonic assisted liquid?liquid microextraction method for determination of Cu, Cd, Ni, Pb and Zn in edible oils was developed. Detection was carried out by flame atomic absorption spectrometry. The influence of main parameters including ultrasonic time and temperature, disperser solvent, volume of extracting solvent and centrifuging time on the extraction efficiency of target analytes were investigated and optimized. In the proposed method, a few microliters of water (containing 3%, v/v, nitric acid) as extracting solvent was injected into the oil sample and mixture transferred to ultrasonic bath. Then, the mixture was centrifuged in order to accelerate in phase separation. Finally, the aqueous phase was removed and delivered to flame atomic absorption spectrometer. Calibration curves for all metals were linear in the range of 5?100 ng/mL. The limit of detections for Cu, Cd, Ni, Pb and Zn were 0.8, 0.3, 0.5, 1.5 and 0.5 ng/mL, respectively. Relative standard deviation (RSD) values were in the range of 0.6?1.9%. The recoveries were in the range of 95.2–101.2% with RSD values ranging from 0.8 to 1.9%. The proposed method was applied successfully for the determination of interested metals in commercial edible oils.     

Cation-exchange separation and colorimetric determination of some elements in trace analysis of platinum-rhodium (10%) alloys

Summary A method of separation and colorimetric determination of trace amounts (10^–4–10^–5%) of Cu, Al, Fe, Bi, Pb, Mn, Cd, Zn, Co, and M in platinum-rhodium (10%) alloys has been developed. The elements to be determined are retained on a column containing the strongly acidic cation-exchanger Amberlite IR-120, from dilute hydrochloric acid medium (p_H 1–1.5), while platinum and rhodium pass through in the form of anionic chloride complexes. The individual metals are eluted and concentrated and then separated by extraction and carrier precipitation. The metals are determined by means of sensitive colorimetrie methods with dithizone (Cu, Bi, Pb, Cd, Zn), eriochromecyanine R (Al), 2-nitroso-1-naphthol (Co),-furildioxime (Ni), 1-(2-pyridylazo)-2-naphthol (Mn), and thiocyanate (Fe). The error of the determination does not exceed 15%.

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Zusammenfassung Eine Trennungs- und Bestimmungsmethode für Spuren (10^–4 bis 10^–5%) von Cu, Al, Fe, Bi, Pb, Mn, Cd, Zn, Co und Ni in PIatm-Rhodium-(10%)-Legierungen wurde ausgearbeitet.Die angeführten Elemente werden mit Amberlit IR-120 aus der verd. salzsauren Lösung (p_H 1 bis 1,5) von Platin und Rhodium getrennt, die als Anionchloridkomplexe im Eluat bleiben. Die einzelnen Metalle werden nach Elution aus ihrer Lösung durch Extraktion bzw. Mitfällung getrennt und kolorimetrisch mit Dithizon (Cu, Bi, Pb, Cd, Zn), Eriochromcyanin R (Al), 2-Nitroso-1-naphthol (Co),-Furildioxim (Ni), 1-(2-Pyridylazo)-2-naphthol (Mn) und Rhodanid (Fo) bestimmt. Der Fehler beträgt weniger als 15%,

     

煤中痕量元素在循环流化床锅炉中的迁移行为与富集特性

对天津市某电厂循环流化床(CFB)锅炉燃用的原煤及燃烧产物底灰、飞灰、细飞灰(≤50 μm)进行痕量元素含量的测定,分析了Be、Zn、Hg、V、Cr、Mn、Co、Ni、Cu、As、Se、Cd、Pb 13种痕量元素在燃烧过程中的迁移行为,揭示了痕量元素在CFB锅炉中的分配、富集特性。结果表明,CFB锅炉中,较低的炉温对于痕量元素的迁移富集产生了较大的影响。由相对富集系数得知,Be、V、Co、Se在底灰中耗散,在飞灰中富集,Zn、Mn倾向于在底灰中富集,元素Cd、Pb、Ni、Cu挥发性较强,在底灰和飞灰中均是耗散。As受钙氧化物影响,挥发性表现并不明显。Hg在底灰和飞灰中相对富集系数均很低,表明Hg在整个燃烧过程中以气态形式排放;Hg、As、Se、V、Cr、Mn、Co、Ni、Cu、Zn、Pb均有向小颗粒物中富集的趋势。根据相对富集系数以及研究的13种元素在低温CFB锅炉中的迁移行为,将这些元素分为三类:A类(E_R<0.1),主要是以气态形式排放元素Hg;B类(0.1R≤0.85),较易挥发元素As、Be、Ni、Cu、Se、Cd、Pb、Co、V;C类(E_R>0.85),主要残留在固体产物中元素Zn、Mn、Cr。     

Electrothermal atomic absorption spectrometric determination of cobalt, copper, lead and nickel traces in aragonite following flotation and extraction separation

A method of determination of Co, Cu, Pb and Ni in nanogram quantities from aragonite is presented. Flotation and extraction of Co, Cu, Pb and Ni is suggested as methods for elimination matrix interferences of calcium. The method of flotation is performed by iron(III) hexamethylenedithiocarbamate, Fe(HMDTC)(3), as a colloid precipitate collector. The liquid-liquid extraction of Co, Cu, Pb and Ni is carried out by sodium diethyldithiocarbamate, NaDDTC, as complexing reagent into methylisobutyl ketone, MIBK. The electrothermal atomic absorption spectrometry (ETAAS) is used for determination of analytes. The detection limits of ETAAS followed by flotation are: 7.8 ng.g(-1) for Co, 17.1 ng.g(-1) for Cu, 7.2 ng.g(-1) for Pb and 9.0 mug.g(-1) for Ni. The detection limits of ETAAS followed by extraction are found to be: 12.0 ng.g(-1) for Co, 51.0 ng.g(-1) for Cu, 24.0 ng.g(-1) for Pb and 21.0 ng.g(-1) for Ni.     

Inorganic species in water and sediments of the Lamone and Marzeno rivers ecosystem

Analytical results are reported for the determination of inorganic species in water and sediments sampled in the Lamone and Marzeno rivers ecosystem. The species determined are Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn, Hg, F-, Cl- Br-, NO3-, SO4--, Na+, K+, Mg++, Ca++, NH4+ in superficial water, and Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Zn, Hg in sediments. For all the elements, in addition to detection limits, precision and accuracy are given: the former, expressed as relative standard deviation (s(r)), and the latter, expressed as relative error (e), were good, being in all cases lower than 6%.     

Application of a method for matrix correction using compton-scattering for the quantitative determination of metals in silica by wavelength dispersive X-ray fluorescence spectroscopy (WDXRF)

Summary A correction method to diminish errors caused by different mass absorption coefficients of the samples is described. Also errors caused by differing device parameters are diminished. The method is used for the determination of Fe, Cr, Ni, Co, Mn, Zn, Cd, Cu, Hg and Pb on chemically modified silica in the g/g-range.

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Anwendung einer Methode zur Matrixkorrektur durch Compton-Streupeaks für die quantitative Bestimmung von Metallen in Kieselgelen mit Hilfe der wellenlängendispersiven Röntgenfluorescenzanalyse (WDXRF)

Zusammenfassung Ein Korrekturverfahren zur Verminderung von Meßfehlern, die durch unterschiedliche Massenabsorptionskoeffizienten der Proben verursacht werden, wird beschrieben. Ebenso werden Fehler durch Schwankungen von Geräteparametern verringert. Die Methode wird benutzt zur Bestimmung von Fe, Cr, Ni, Cd, Co, Mn, Zn, Cu, Hg und Pb auf chemisch modifizierten Kieselgelen im g/g-Bereich.

     

微波辅助消解-电感耦合等离子体原子发射光谱法(ICP-AES)测定几种血藤中17种元素

建立电感耦合等离子体原子发射光谱法(ICP-AES)测定血藤类中药中K,Ca,Mg,P,Sr,Fe,Mn,Zn,Cu,Co,Cr,Al,Ba,Ni,As,Pb和Cd 17种常量和微量元素含量的分析方法。样品用微波辅助消解,ICP-AES法检测几种血藤中17种元素的含量,方法的检出限为0.000 03~0.009 81μg/mL,加标回收率88.37%~110.00%,相对标准偏差(RSD)均小于5.0%,方法可快速、灵敏、准确测定血藤类中药中多种常量、微量元素的含量。血藤样品中除含有人体必需的常量元素K,Ca,Mg外,还含有Fe,Zn,Mn,Cr,Co等必需的微量元素和其它元素P,Ni,Ba,Al,Sr,Pb,Cd,Ba等。     

Amberlite XAD-7 impregnated with Xylenol Orange: a chelating collector for preconcentration of Cd(II), Co(II), Cu(II), Ni(II), Zn(II) and Fe(III) ions prior to their determination by flame AAS

A new chelating resin, Xylenol Orange coated Amberlite XAD-7, was prepared and used for preconcentration of Cd(II), Co(II), Cu(II), Fe(III), Ni(II) and Zn(II) prior to their determination by flame atomic absorption spectrophotometry. The optimum pH values for quantitative sorption of Cd(II), Co(II), Cu(II), Fe(III), Ni(II) and Zn(II) are 4.5-5.0, 4.5, 4.0-5.0, 4.0, 5.0 and 5.0-7.0, respectively, and their desorptions by 2 mol L(-1) HCl are instantaneous. The sorption capacity of the resin has been found to be 2.0, 2.6, 1.6, 1.6, 2.6 and 1.8 mg g(-1) of resin for Cd, Co, Cu, Fe, Ni and Zn, respectively. The tolerance limits of electrolytes, NaCl, NaF, NaI, NaNO3, Na2SO4 and of cations, Mg2+ and Ca2+ in the sorption of the six metal ions are reported. The preconcentration factor was between 50 and 200. The t1/2 values for sorption are found to be 5.3, 2.9, 3.2, 3.3, 2.5 and 2.6 min for the six metals, respectively. The recoveries are between 96.0 and 100.0% for the different metals at preconcentration limits between 10 to 40 ng mL(-1). The preconcentration method has been applied to determine the six metal ions in river water samples after destroying the organic matter (if present in very large amount) with concentrated nitric acid (RSD < or = 8%, except for Cd for which it is upto 12.6%) and cobalt content of vitamin tablets with RSD of approximately 3.0%.     

Capillary gas chromatographic analysis of pyrrolidinedithiocarbamate metal chelates

Pyrrolidinedithiocarbamate (PDTC) chelates of Zn(II), Cu(II), Ni(II), Co(III), Fe(III), Mn(II), Cr(III), and VO(II) were analysed by capillary GC on a DB-1701 column (30 m x 0.25 mm id) with flame ionisation detection (FID). Linear calibrations were attained within "1-30 microg/mL" for Ni(II), Fe(III), Mn(II), Cr(III), Cu(II), and VO(II), and within "2-50 microg/mL" for Co(III) and Zn(II). The limits of detection were in the "150-500 ng/mL" range, corresponding to 15-50 pg amounts reaching the FID system. The optimised method was applied to the determination of Cu(II) and Ni(II) in coins, and that of Zn(II), Cu(II), Ni(II), Fe(III), Mn(II), Cr(III), and VO(II) in pharmaceutical preparations with relative standard deviations within 1.1-5.2%. The results obtained are in good agreement with sewage water samples and the declared values for the pharmaceutical formulations, or with the results of AAS of metal contents in coins, pharmaceutical preparations, and sewage water samples.     

Synthesis of bis(amino alcohol)oxalamides and their usage for the preconcentration of trace metals by cloud point extraction.

C(2)-Symmetric two bis(amino alcohol)oxalamides (diamidediols) were synthesized and fully characterized. A new method was developed and successfully applied for the simultaneous preconcentration of both trace and toxic metals in water, by using C(2)-symmetric compounds. Under the optimum experimental conditions (i.e. pH = 10.0 +/- 0.2, 2.75 x 10(-3) mol L(-1) N,N'-bis[(1R)-1-ethyl-2-hydroxyethyl]ethanediamide (DAD1), 1.75 x 10(-3) mol L(-1) N,N'-bis[(1S)-1-benzyl-2-hydroxyethyl]-ethanediamide (DAD2), 0.10% w/v octylphenoxy-polyethoxyethanol (Triton X-114)), calibration graphs were linear in the range of 2.5 - 25.0 ng mL(-1) for Cu and Cd, 5.0 - 25.0 ng mL(-1) for Co and Ni. The enrichment factors were 18, 23, 18 and 20 for Cd, Cu, Co and Ni in the case of DAD1, respectively; 20, 22, 17 and 20 for Cd, Cu, Co and Ni in the case of DAD2. The limits of detection for DAD1 were found to be 0.45, 0.50, 1.25 and 0.60 ng mL(-1) for Cd, Cu, Co and Ni, respectively, and for DAD2 were found to be 0.44, 0.25, 0.60 and 1.55 ng mL(-1) for Cd, Cu, Co and Ni, respectively. The developed method was applied to the determination of Cu, Cd, Co and Ni in water samples and certified reference materials with satisfactory results.     

Determination of trace metals in seawater by graphite furnace atomic absorption spectrometry with preconcentration on silica-immobilized 8-hydroxyquinoline in a flow-system

Summary A flow-system utilizing a miniature column packed with silica-immobilized 8-hydroxyquinoline (I-8-HOQ) was used for the preconcentration of Cd, Pb, Zn, Cu, Fe, Mn, Ni, and Co from seawater prior to their determination by graphite furnace atomic absorption spectrometry (GFAAS). Enrichment factors sufficient to permit the analysis of an open ocean seawater reference material using 50 ml sample volumes (100 ml for Co determinations) were obtained. Recoveries of the above elements from seawater averaged 93% (range 87–97%) with absolute blanks ranging between 0.04 ng (Ni) and 4.0 ng (Fe). Estimated detection limits for these elements vary from 0.2 ng l^–1 (Co) to 40 ng l^–1 (Fe) based on a 50 ml sample volume (100 ml for Co).

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Bestimmung von Spurenmetallen in Meereswasser durch Graphitofen-AAS mit Anreicherung an Kieselgel-immobilisiertem 8-Hydroxychinolin in einem Durchflu\system