Optimisation of plutonium separations using TEVA cartridges and ICP-MS/MS analysis for applicability to large-scale studies in tropical soils (original) (raw)
Environmental Study of Fallout Plutonium in Soils from
The distributions of 2SSpu and 2~9+ 24°pu in surface soils from the Piemonte region were measured and the main factors influencing Pu concentrations investigated. Rainfall, altitude and the concentration of organic matter play an important role, while other soil parameters (pedology, lithology and geomorphology) are of lesser significance. Contour maps of the surface soil concentrations of 238 pu and 239+24°pu are reported.
Analytica Chimica Acta, 1998
A rapid and highly precise method, which uses a borate fusion, of U and Pu determination in soils, sediments and other materials is described. The chemical separation steps are optimised by using an anion resin column stacked on an extraction chromatography column (Eichrom Industries UTEVA resin). The whole procedure was streamlined to measure 700 soil samples in 10 weeks as part of an urgent environmental monitoring programme. Uranium was measured using thermal ionisation mass spectrometry with a precision of 0.2% at the 95% uncertainty level. Pu was measured using alpha spectrometry with a precision of approximately 10% at the 95% uncertainty level. The method can be applied successfully to a wide range of sample types and other actinide elements (Th, Am, etc.) can also be effectively included in the analytical scheme. The whole method has been critically evaluated by measuring a range of international reference samples.
2003
The removal of plutonium from Nevada Test Site (NTS) area soils has previously been attempted using various combinations of attrition scrubbing, size classification, gravitybased separation, flotation, air flotation, segmented gate, bioremediation, magnetic separation and vitrification. Results were less than encouraging, but the processes were not fully optimized. To support additional vendor treatability studies soil from the Clean Slate II site (located on the Tonopah Test Range, north of the NTS) were characterized and tested. These particular soils from the NTS are contaminated primarily with plutonium-239/240 and Am-241. Soils were characterized for Pu-239/240, Am-241 and gross alpha. In addition, wet sieving and the subsequent characterization were performed on soils before and after attrition scrubbing to determine the particle size distribution and the distribution of Pu-239/240 and gross alpha as a function of particle size. Sequential extraction was performed on untreated soil to provide information about how tightly bound the plutonium was to the soil. Magnetic separation was performed to determine if this could be useful as part of a treatment approach. The results indicate that about a 40% volume reduction of contaminated soil should be achievable by removing the >300 um size fraction of the soil. Attrition scrubbing does not effect particle size distribution, but does result in a slight shift of plutonium distribution to the fines. As such, attrition scrubbing may be able to slightly increase the ability to separate plutonium-contaminated particles from clean soil. This could add another 5-10% to the mass of the clean soil, bringing the total clean soil to 45-50%. Additional testing would be needed to determine the value of using attrition scrubbing as well as screening the soil through a sieve size slightly smaller than 300 um. Since only attrition scrubbing and wet sieving would be needed to attain this, it would be good to conduct this investigation. Magnetic separation did not work well. The sequential extraction studies indicated that a significant amount of plutonium was soluble in the "organic" and "resistant" extracts. As such chemical extraction based on these or similar extractants should also be considered as a possible treatment approach.
PU and NP analysis of soil and sediment samples with ICP-MS
Applied Radiation and Isotopes, 2009
A method to analyse Pu and Np was optimised to achieve low detection limits and high sample throughput. Soil and sediment samples were ashed and digested with a borate fusion. After dissolving the melt in nitric acid, Pu and Np were separated on a TEVA extraction chromatopraphy column. It was measured with a sector field ICP-MS. Detection limits in soils and sediments as low as 1 Â10 À15 g/g for Pu and Np were achieved. The method was applied to reference materials, soil profiles from Switzerland and sediment samples from the river Yenisei (RU), where radioactive nuclides have been discharged.
Atomic Energy, 1997
The principal sources of plutonium and americium entering the environment are tests of nuclear weapons, the accident at the Chernobyl nuclear power station, and discharges from radiochemical factories. It is necessary to monitor the contamination of soil these produce from the levels caused by global radioactive fallout. The 241pu content in plutonium contaminating soil can vary by an appreciable factor (see ). This determines the contribution of 241Anl to the total c~ activity of the soil or of a sample prepared from it.
J. Anal. At. Spectrom., 2004
An analytical method for the determination of plutonium concentration and its isotope ratio at ultratrace level in natural water by inductively coupled plasma mass spectrometry (ICP-MS) is proposed. In order to preconcentrate Pu and to avoid matrix effects and clogging effects on the cones during the mass spectrometric measurements, an effective Pu separation procedure (on TEVA resin) from the matrix was applied. Studies of the separation procedure for 2.1 pg of 242 Pu spiked into 100 L of lake water from the Sea of Galilee result in a recovery of 62%. The detection limits of 239 Pu in 100 L lake water were determined as 1 6 10 219 g mL 21 and 3 6 10 220 g mL 21 using ICP-SFMS and MC-ICP-MS, respectively. 239 Pu was detected in the Sea of Galilee at a concentration level of about 3.6 6 10 219 g mL 21 with a 240 Pu/ 239 Pu isotope ratio of 0.17. This measured plutonium isotope ratio is the most probable evidence of plutonium contamination of the Sea of Galilee as a result of global nuclear fallout after the nuclear weapons tests in the sixties. This paper discusses applications of double-focusing sector field ICP-MS with single and multiple ion collection for the quantitative determination of plutonium and its isotope ratio at the 10 219 g mL 21 level in natural water.
Rapid fusion method for the determination of Pu, Np, and Am in large soil samples
Journal of Radioanalytical and Nuclear Chemistry, 2015
A new rapid sodium hydroxide fusion method for the preparation of 10-20 g soil samples has been developed by the Savannah River National Laboratory (SRNL). The method enables lower detection limits for plutonium, neptunium, and americium in environmental soil samples. The method also significantly reduces sample processing time and acid fume generation compared to traditional soil digestion techniques using hydrofluoric acid. Ten gram soil aliquots can be ashed and fused using the new method in 1-2 hours, completely dissolving samples, including refractory particles. Pu, Np and Am are separated using stacked 2 mL cartridges of TEVA and DGA Resin and measured using alpha spectrometry. The method can be adapted for measurement by inductively-coupled plasma mass spectrometry (ICP-MS). Two 10 g soil aliquots of fused soil may be combined prior to chromatographic separations to further improve detection limits. Total sample preparation time, including chromatographic separations and alpha spectrometry source preparation, is less than 8 hours.