Preconcentration Of Plutonium Research Articles

Determination of Ultra-Low Level Plutonium Isotopes in Large Volume Environmental Water Samples

Plutonium is an important artificial element, 239 Pu and 240 Pu are two major radioisotopes of plutonium in the environment released by human nuclear activities. Due to their high radiotoxicity and bio-toxicity, the determination of these radionuclides is critical in view of radiation protection and environmental radioactivity. It is still a major challenge to accurately determine these radionuclides in environmental water samples due to their extremely low concentrations. In this work, a sensitive analytical method for determination of 239 Pu and 240 Pu in environmental water samples was reported. By co-precipitation of plutonium with Ti(OH) 3 followed by separation of plutonium using extraction chromatography with TEVA resin, a recovery of more than 80% for plutonium and decontamination factor of 1.3 × 10 5 for uranium were achieved. A triple quadrupole inductively coupled plasma mass spectrometry (ICP-MS) with dynamic collision/reaction cell was used for measurement of plutonium isotopes. By using NH 3 -He double gasses as collision/reaction gas, 238 U 1 H + polyatomic ion interference to measurement of 239 Pu was significantly suppressed and the final abundance sensitivity of 238 U to m/z 239 was reduced to < 1 × 10 –11 , and sensitivity of 239 Pu was improved to 990 cps/(pg/g). For 20 L water sample, the detection limits of the method for 239 Pu and 240 Pu reached 1.28 × 10 –7 Bq/L and 1.38 × 10 –7 Bq/L, respectively, which enabled accurate determination of 239 Pu and 240 Pu in normal environmental water samples. The developed method was successfully applied to determine 239 Pu and 240 Pu in the spiked water and real environmental water samples, and the results indicated that this method was reliable and could be practically applied. A sensitive method for determination of ultra-low level 239 Pu and 240 Pu was established by pre-concentration of plutonium from large volume water using Ti(OH) 3 co-precipitation, purification for plutonium using extraction chromatography with TEVA resin and triple quadrupole ICP-MS measurement of plutonium isotope. NH 3 -He was used as reaction gas for elimination of uranium hydride interference and increasing the measurement sensitivity using collision focusing. The method was successfully applied for analysis of environmental water samples from China.

Characterization of the behavior and mechanism of electrochemical pre-concentration of plutonium from aqueous solution

Radiochemical analyses usually require sample preparation typically including a pre-concentration step. Previous work was completed showing the success of electrochemical pre-concentration, as applied to 4f-elements, in reducing the time necessary to pre-concentrate a sample. However, these studies did not include the more electrochemically diverse 5f-elements. The objective of this work was to investigate the ability of a multivalent actinide, plutonium (Pu), to be electrochemically pre-concentrated while maximizing the efficiency of the method and proposing a mechanism of pre-concentration. In an aqueous solution with a mercury film electrode, Pu can successfully pre-concentrate and was proposed to do so via amalgamation.

RAPID DETERMINATION OF 237NP AND PLUTONIUM ISOTOPES IN URINE BY INDUCTIVELY-COUPLED PLASMA MASS SPECTROMETRY AND ALPHA SPECTROMETRY

A new rapid separation method was developed for the measurement of plutonium and neptunium in urine samples by inductively-coupled plasma mass spectrometry (ICP-MS) and/or alpha spectrometry with enhanced uranium removal. This method allows separation and preconcentration of plutonium and neptunium in urine samples using stacked extraction chromatography cartridges and vacuum box flow rates to facilitate rapid separations. There is an increasing need to develop faster analytical methods for emergency response samples. There is also enormous benefit to having rapid bioassay methods in the event that a nuclear worker has an uptake (puncture wound, etc.) to assess the magnitude of the uptake and guide efforts to mitigate dose (e.g., tissue excision and chelation therapy). This new method focuses only on the rapid separation of plutonium and neptunium with enhanced removal of uranium. For ICP-MS, purified solutions must have low salt content and low concentration of uranium due to spectral interference of (238)U(1)H(+) on m/z 239. Uranium removal using this method is enhanced by loading plutonium and neptunium initially onto TEVA resin, then moving plutonium to DGA resin where additional purification from uranium is performed with a decontamination factor of almost 1×10(5). If UTEVA resin is added to the separation scheme, a decontamination factor of ~3 × 10(6) can be achieved.

Multi-isotopic determination of plutonium ( 239Pu, 240Pu, 241Pu and 242Pu) in marine sediments using sector-field inductively coupled plasma mass spectrometry

Among the transuranic elements present in the environment, plutonium isotopes are mainly attached to particles, and therefore they present a great interest for the study and modelling of particle transport in the marine environment. Except in the close vicinity of industrial sources, plutonium concentration in marine sediments is very low (from 10 −4 ng kg −1 for 241Pu to 10 ng kg −1 for 239Pu), and therefore the measurement of 238Pu, 239Pu, 240Pu, 241Pu and 242Pu in sediments at such concentration level requires the use of very sensitive techniques. Moreover, sediment matrix contains huge amounts of mineral species, uranium and organic substances that must be removed before the determination of plutonium isotopes. Hence, an efficient sample preparation step is necessary prior to analysis. Within this work, a chemical procedure for the extraction, purification and pre-concentration of plutonium from marine sediments prior to sector-field inductively coupled plasma mass spectrometry (SF-ICP-MS) analysis has been optimized. The analytical method developed yields a pre-concentrated solution of plutonium from which 238U and 241Am have been removed, and which is suitable for the direct and simultaneous measurement of 239Pu, 240Pu, 241Pu and 242Pu by SF-ICP-MS.

Preconcentration of plutonium and americium using the Actinide-CUTM Resin for human tissue analysis

A method for the preconcentration of Am and Pu from human tissue solutions (liver, lung, bone etc) using the Actinide-CU Resin (ElChroM Industries) has been developed for their alpha-spectrometric determination. With near 100% recoveries were obtained by preconcentration, subsequent decomposition methods for eluent were developed. Good agreement for Pu and Am determination with the USTUR anion-exchange/solvent extraction method was demonstrated using previously analyzed human tissue solutions and NIST SRMs. The advantages of the preconcentration method applied to human tissue analysis are simplicity of operation, shorter analysis time compared to anion exchange/solvent extraction methods, and capacity to analyze large tissue samples (up to 15 g bone ash per analysis and 500 g soft tissue).