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A comparison of continuous pneumatic nebulization and flow injection-direct injection nebulization for sample introduction in inductively coupled plasma-mass spectrometry

Description: Dilute nitric acid blanks and solutions containing Ni, Cd, Pb, and U (including two laboratory waste samples) were analyzed eighteen times over a two-month period using inductively coupled plasma-mass spectrometry (ICP-MS). Two different sample introduction techniques were employed: flow injection-direct injection nebulization (FI-DIN) and continuous pneumatic nebulization (CPN). Using comparable instrumental measurement procedures, FI-DIN analyses were 33% faster and generated 52% less waste than CPN analyses. Instrumental limits of detection obtained with FI-DIN and CPN were comparable but not equivalent (except in the case of Pb) because of nebulizer-related differences in sensitivity (i.e., signal per unit analyte concentration) and background. Substantial and statistically significant differences were found between FI-DIN and CPN Ni determinations, and in the case of the laboratory waste samples, there were also small but statistically significant differences between Cd determinations. These small (2 to 3%) differences were not related to polyatomic ion interference (e.g., {sup 95}Mo{sup 16}O{sup +}), but in light of the time savings and waste reduction to be realized, they should not preclude the use of FI-DIN in place of CPN for determination of Cd, Pb, U and chemically.
Date: August 1, 1995
Creator: Crain, J.S. & Kiely, J.T.
Partner: UNT Libraries Government Documents Department

A comparison of continuous pneumatic nebulization and flow injection-direction injection nebulization for sample introduction in inductively coupled plasma-mass spectrometry

Description: Samples containing Ni, Cd, Pb, and U were analyzed eighteen times over a two-month period using inductively coupled plasma-mass spectrometry (ICP-MS). Sample introduction was accomplished by either flow injection-direct injection nebulization (FI-DIN) or continuous pneumatic nebulization (CPN). Using comparable instrumental measurement procedures, FI-DIN analyses were 33% faster and generated 52% less waste than CPN analyses. Instrumental limits of detection obtained with FI-DIN and CPN were comparable but not equivalent (except in the case of Pb) because of nebulizer-related differences in sensitivity (i.e., signal per unit analyte concentration) and background. Substantial and statistically significant differences were found between FI-DIN and CPN Ni determinations, and in the case of laboratory waste samples, there were also small but statistically significant differences between Cd determinations. These small (2 to 3%) differences were not related to polyatomic ion interference (e.g., {sup 95}Mo{sup 16}O{sup +}), but in light of the time and waste savings to be realized, they should not preclude the use of FI-DIN in place of CPN for determination of Cd, Pb, U, and similar elements present at trace concentrations.
Date: August 1, 1997
Creator: Crain, J.S. & Kiely, J.T.
Partner: UNT Libraries Government Documents Department

Determination of labile copper, cobalt, and chromium in textile mill wastewater

Description: Copper, chromium, and cobalt species present in filtered wastewater effluent were separated by cation exchange and reverse phase chromatography. Three sample fractions were obtained: one containing metal cations (i.e., trivalent Cr, divalent Cu, and divalent Co), one containing organic species (including metallized dyes), and one containing other unretained species. The metal content of each fraction was determined by inductively coupled plasma atomic emission spectroscopy (ICP-AES). The sum of the corrected data was compared to the metal content of a filtered effluent aliquot digested totally with fuming sulfuric acid. Other aliquots of the filtered effluent were spiked with the metals of interest and digested to confirm chemical yield and accuracy. Method detection limits were consistently below 20 {mu}g L{sup -1} for Cu, 30 {mu}g L{sup -1} for Co, and 10 {mu}g L{sup -1} for Cr. Spike recoveries for undifferentiated Cu and Cr were statistically indistinguishable from unity; although Co spike recoveries were slightly low ({approximately}95%), its chemical yield was 98%. Copper retention on the sodium sulfonate cation exchange resin was closely correlated with the [EDTA]/[Cu] ratio, suggesting that metals retained upon the cation exchange column were assignable to labile metal species; however, mass balances for all three elements, though reasonable ({approximately}90%), were significantly different from unity. Mechanical factors may have contributed to the material loss, but other data suggest that some metal species reacted irreversibly with the reverse phase column. 3 refs., 2 figs., 4 tabs.
Date: January 1, 1997
Creator: Crain, J.S.; Essling, A.M. & Kiely, J.T.
Partner: UNT Libraries Government Documents Department

Waste minimization in analytical methods

Description: The US Department of Energy (DOE) will require a large number of waste characterizations over a multi-year period to accomplish the Department`s goals in environmental restoration and waste management. Estimates vary, but two million analyses annually are expected. The waste generated by the analytical procedures used for characterizations is a significant source of new DOE waste. Success in reducing the volume of secondary waste and the costs of handling this waste would significantly decrease the overall cost of this DOE program. Selection of appropriate analytical methods depends on the intended use of the resultant data. It is not always necessary to use a high-powered analytical method, typically at higher cost, to obtain data needed to make decisions about waste management. Indeed, for samples taken from some heterogeneous systems, the meaning of high accuracy becomes clouded if the data generated are intended to measure a property of this system. Among the factors to be considered in selecting the analytical method are the lower limit of detection, accuracy, turnaround time, cost, reproducibility (precision), interferences, and simplicity. Occasionally, there must be tradeoffs among these factors to achieve the multiple goals of a characterization program. The purpose of the work described here is to add waste minimization to the list of characteristics to be considered. In this paper the authors present results of modifying analytical methods for waste characterization to reduce both the cost of analysis and volume of secondary wastes. Although tradeoffs may be required to minimize waste while still generating data of acceptable quality for the decision-making process, they have data demonstrating that wastes can be reduced in some cases without sacrificing accuracy or precision.
Date: May 1, 1995
Creator: Green, D.W.; Smith, L.L.; Crain, J.S.; Boparai, A.S.; Kiely, J.T. & Yaeger, J.S. Schilling, J.B.
Partner: UNT Libraries Government Documents Department

Determination of naturally-occurring actinides and their progeny in fresh water using inductively coupled plasma-mass spectrometry and batch separation

Description: The objective of this report is to show the use of ICP-MS in combination with appropriate preparative techniques for the determination of actinide elements in the environment. It examines and identifies the sample introduction and preparation techniques necessary to achieve required detection limits and mitigate interferences. This volume contains a set of viewgraphs.
Date: May 1, 1995
Creator: Crain, J.S.; Yaeger, J.S.; Alvarado, J.A.; Smith, L.L.; Kiely, J.T. & Smith, F.G.
Partner: UNT Libraries Government Documents Department

Actinides at the crossroads: ICP-MS or alpha spectrometry?

Description: The report contains viewgraphs only that summarize the following: Why turn to mass spectrometry for radiochemical measurements; What might be some advantages of using ICP mass spectrometry; Sensitivity of ETV-ICP-MS relative to decay counting (versus half-life); ICP-MS instrument detection limits for dissolved actinide isotopes; Effect of dissolved solids on USN-ICP-MS analysis; Polyatomic ion interferences in ICP-MS actinide measurements; Effect of operating conditions on uranium and protonated uranium signal; ICP mass spectrometry performance in actinide determinations; Determination of actinide elements in soil; Leachable Th-230 and Pu-239 in soil as determined by ICP-MS and alpha spectrometry; Leachable U-234 and U-238 in soil by ICP-MS and alpha spectrometry; Determination of uranium isotopic composition on smears; Activity ratios (U-234/U-238) as determined by mass spectrometry and alpha spectrometry; Uranium isotopic abundances as determined by TIMS and ICP-MS; and Comparison of uranium atom percentages determined by TIMS and ICP-MS. It is concluded that isotope dilution and radiochemical preparative techniques work well in radioanalytical applications of ICP-MS; radioanalytical ICP-MS data are equivalent to data from standard methods (TIMS, alpha spectrometry); and applications in radiation protection and earth sciences are certain to expand further.
Date: December 31, 1995
Creator: Crain, J.S.; Yaeger, J.S.; Smith, F.P.; Alvarado, J.A.; Smith, L.L.; Kiely, J.T. et al.
Partner: UNT Libraries Government Documents Department

Secondary waste minimization in analytical methods

Description: The characterization phase of site remediation is an important and costly part of the process. Because toxic solvents and other hazardous materials are used in common analytical methods, characterization is also a source of new waste, including mixed waste. Alternative analytical methods can reduce the volume or form of hazardous waste produced either in the sample preparation step or in the measurement step. The authors are examining alternative methods in the areas of inorganic, radiological, and organic analysis. For determining inorganic constituents, alternative methods were studied for sample introduction into inductively coupled plasma spectrometers. Figures of merit for the alternative methods, as well as their associated waste volumes, were compared with the conventional approaches. In the radiological area, the authors are comparing conventional methods for gross {alpha}/{beta} measurements of soil samples to an alternative method that uses high-pressure microwave dissolution. For determination of organic constituents, microwave-assisted extraction was studied for RCRA regulated semivolatile organics in a variety of solid matrices, including spiked samples in blank soil; polynuclear aromatic hydrocarbons in soils, sludges, and sediments; and semivolatile organics in soil. Extraction efficiencies were determined under varying conditions of time, temperature, microwave power, moisture content, and extraction solvent. Solvent usage was cut from the 300 mL used in conventional extraction methods to about 30 mL. Extraction results varied from one matrix to another. In most cases, the microwave-assisted extraction technique was as efficient as the more common Soxhlet or sonication extraction techniques.
Date: July 1, 1995
Creator: Green, D.W.; Smith, L.L.; Crain, J.S.; Boparai, A.S.; Kiely, J.T.; Yaeger, J.S. et al.
Partner: UNT Libraries Government Documents Department

New analytical methods to minimize secondary waste

Description: The US Department of Energy (DOE) will require a large number of waste characterizations over a multi-year period to accomplish the Department`s goals in environmental restoration and waste management. Estimates vary, but two million analyses annually are expected. The waste generated by the analytical procedures used for characterizations is a significant source of new DOE waste. Success in reducing the volume of secondary waste and the costs of handling this waste would significantly decrease the overall cost of this DOE program. We have chosen to review the analytical procedures in three areas -- sample injection for inorganic analysis, dissolution of waste samples for radiochemical analysis, and sample preparation for analysis of organic constituents.
Date: July 1, 1995
Creator: Green, D.W.; Smith, L.L.; Cain, J.S.; Boparai, A.S.; Kiely, J.T.; Yaeger, J.S. et al.
Partner: UNT Libraries Government Documents Department

Arsenic speciation in soil using high performance liquid chromatography/inductively coupled plasma/mass spectrometry

Description: A method has been developed to identify and quantify As(III), As(V), and organoarsenic compounds in soil samples from the Rocky Mountain Arsenal (RMA) by high performance liquid chromatography/inductively coupled plasma/mass spectrometry (HPLC/ICP/MS). The soils were extracted using tetrabutylammonium hydroxide (TBAH) and sonication. The percentages of As(III), As(V), and organoarsenic species extracted from soil samples were 30, 50, and 100 respectively. The arsenic species were not altered during the extraction process. They were separated by reversed-phase, ion-pairing, HPLC using a microbore Inertsil-ODS{trademark} column. The HPLC column effluent was introduced into an ICP/MS system using a direct injection nebulizer (DIN). Detection limits of less than 1 pg were readily obtained for each arsenic species. Internal standards are recommended to increase accuracy and precision. Soil samples spiked with arsenic oxide, sodium arsenate, dimethylarsinic acid (DMAA), and chlorovinyl arsenious acid (CVAA) were extracted, identified and quantified with the HPLC/ICP/MS system. The soil samples were analyzed in support of the analytical needs of a thermal desorption treatability study being conducted at the RMA.
Date: August 1, 1996
Creator: Bass, D. A.; Yaeger, J. S.; Parish, K. J.; Crain, J. S.; Kiely, J. T.; Gowdy, M. J. et al.
Partner: UNT Libraries Government Documents Department

Detecting and quantifying lewisite degradation products in environmental samples using arsenic speciation

Description: This report describes a unique method for identifying and quantifying lewisite degradation products using arsenic (III) and arsenic (IV) speciation in solids and in solutions. Gas chromatographic methods, as well as high-performance liquid chromatographic methods are described for separation of arsenic species. Inductively coupled plasma-mass spectrographic methods are presented for the detection of arsenic.
Date: December 31, 1995
Creator: Bass, D.A.; Yaeger, J.S.; Kiely, J.T.; Crain, J.S.; Shem, L.M.; O`Neill, H.J. et al.
Partner: UNT Libraries Government Documents Department

Arsenic speciation using high performance liquid chromatography-inductively coupled plasma-mass spectrometry

Description: A method has been developed by Argonne National Laboratory to identify and quantify As(III), As(V), and organoarsenic compounds in environmental samples. A arsenic species were separated by reversed-phase, ion-pairing, HPLC using a microbore Inertsil-ODS{trademark} column. Only 1 {micro}L of sample was injected on the column, and the mobile phase flow rates were typically on the order of 40 {micro}L/min. The HPLC mobile phase was a mixture of methanol and tetrabutylammonium hydroxide (TBAH), and the column effluent was introduced into an ICP-mass spectrometer using direct injection nebulization. Detection limits of less than 1 pg As (as injected on the column) were easily obtained for each arsenic species. The effect of changes in mobile phase composition and ICP-MS conditions will be described, as well as quality control measures, e.g., the use of surrogates, internal standards, and matrix spikes. Precision and accuracy information will be presented from the analysis of aqueous standards and soil extracts that were spiked with arsenic oxide [As(III)], sodium arsenate [As(V)], dimethylarsinic acid (DMAA), or chlorovinyl arsenious acid (CVAA). The authors believe that these data demonstrate the utility of this technique for the sensitive determination of arsenic species present in water or soil.
Date: August 1995
Creator: Bass, D. A.; Yaeger, J. S.; Crain, J. S.; Kiely, J. T.; Parish, K. J.; Gowdy, M. J. et al.
Partner: UNT Libraries Government Documents Department