Quantitative Determination Of Uranium Research Articles

Quantitative Determination of Uranium with UV-Visible Spectroscopy in Nitrated Media at High Concentration

Quantitative Determination of Uranium with UV-Visible Spectroscopy in Nitrated Media at High Concentration

Rapid and interference free determination of ultra trace level of uranium in potable water originating from different geochemical environments by ICP-OES

Direct determination of uranium in the concentration range of 8 μg L−1 to mg L−1 in water samples originating from different geochemical environments has been done using Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES). Uranium detection with 2–3% RSD (relative standard deviation) has been achieved in water samples by optimizing the plasma power, argon and sheath gas flow. These parameters were optimized for three different emission lines of uranium at 385.958, 409.014 and 424.167 nm. Interference arising due to the variation in concentration of bicarbonate, sodium chloride, calcium chloride, Fe and dissolved organic carbon (DOC) on the determination of uranium in water samples was also cheeked as these are the elements which vary as per the prevailing geochemical environment in groundwater samples. The concentration of NaHCO3, CaCl2 and NaCl in water was varied in the range 0.5–2.0%; whereas Fe ranged between 1 and 10 μg mL−1 and DOC between 0.1–1%. No marked interference in quantitative determination of uranium was observed due to elevated level of NaHCO3, CaCl2 and NaCl and Fe and DOC in groundwater samples. Concentration of uranium was also determined by other techniques like adsorptive striping voltametry (AdSv); laser fluorimetry and alpha spectrometry. Results indicate distinct advantage for uranium determination by ICP-OES compare to other techniques.

Quantitative determination of uranium and europium in glass matrix by laser-induced breakdown spectroscopy

Laser-induced breakdown spectroscopy was applied to the quantitative determination of the elemental composition of glass samples containing U and Eu as a surrogate for highly radioactive glass waste. The emission intensities of both major and minor elements in the samples were measured simultaneously in the wavelength range from 200 to 780 nm by using an echelle spectrometer. Calibration curves for the concentration determination were obtained from the emission intensities at 358.488 nm for U I, and 459.403 nm for Eu I. Limits of detection for U and Eu were ~ 150 and ~ 4.2 parts per million, respectively.

Rapid separation of lanthanides and actinides on small particle based reverse phase supports

Abstract This paper presents the results on the use of short columns (3−5 cm long) with small particle size (1.8 μm) for high performance liquid chromatographic separation of individual lanthanides and uranium from plutonium as well as uranium from thorium to achieve rapid separations i.e. separation time as short as 3.6 min for individual lanthanides, 1 min for thorium-uranium and 4.2 min for uranium from plutonium. These advantages can be exploited to significantly reduce analysis time, liquid waste generation as well as dose to operator when radioactive samples are analysed e.g. burn-up determination. In the present work, a dynamic ion-exchange chromatographic separation technique was employed using camphor-10-sulfonic acid (CSA) as the ion-pairing reagent and α-hydroxy isobutyric acid (α-HIBA) as the complexing reagent for the isolation of individual lanthanides as well as the separation of uranium from thorium. Uranium was separated from Pu(III) as well as Pu(IV) by reverse phase HPLC technique. The reverse phase HPLC was also investigated for the isolation and quantitative determination of uranium from thorium as well as lanthanide group from uranium. The dynamic ion-exchange technique using small particle support was demonstrated for measuring the concentrations of lanthanide fission products such as La, Ce, Pr, Nd and Sm in the dissolver solution of fast reactor fuel. Similarly, the assay of uranium in the dissolver solution of fast reactor was carried out using reverse phase HPLC technique. The rapid separation technique using reverse phase HPLC was also demonstrated for separation of lanthanides as a group from uranium matrix; samples of LiCl-KCl eutectic salt containing chlorides of lanthanides in uranium matrix (typically 1:2000) were analysed.

Fission track estimation of uranium concentrations in liquid homeopathic medicine samples

The ingestion of excessive amount of uranium in homeopathic medicines can damage human's kidneys by preventing normal elimination of urea and other waste products and can cause renal dysfunction. Quantitative determination of uranium in medicines is, therefore, very important. Fission track technique has been applied for the estimation of uranium concentration in homeopathic medicine samples collected from local market. The technique involved simultaneous irradiation of medicine samples and a standard, in contact with track detectors, with thermal neutrons and counting of the fission tracks produced in the detectors as a result of (n, f) nuclear reaction. Uranium concentration in the medicine samples varied from ( 0.003 ± 0.001 ) mg L - 1 to ( 0.297 ± 0.010 ) mg L - 1 with an average value of ( 0.020 ± 0.001 ) mg L - 1 . The observed concentrations were less than the permissible intake level of uranium. So, general public is at no risk while using these medicines for treatment purposes.

Separation and quantification of 238U, 232Th and rare earths in monazite samples by ion chromatography coupled with on-line flow scintillation detector

An alternative procedure has been described for efficient separation and quantitative determination of uranium (U), thorium (Th) and rare earth elements (REEs) in monazite mineral by high performance ion chromatographic system (IC). Different variables affecting the distribution coefficient, the retention and hence separation efficiency such as eluent flow rate and concentrations of HCl and ammonium sulfate (NH 4) 2SO 4 containing the mobile phase were studied. The developed separation protocol of U, Th and REEs was optimized using an Ion Pac CS5 separation column followed by post-column derivatization reaction with Arsenaso III and UV–VIS spectrophotometeric detection. Comparative evaluation of U, Th and REEs concentration in monazite mineral was demonstrated using two different on-line detection modes including flow through cell scintillation detector (FSD) and UV–VIS spectrophotometer. Response of the FSD was found to be linear over the full range of activities investigated (4–100 Bq). The lower limits of detection (LLD) for the investigated radionuclides were 3.0±0.1 Bq for 238U and 6.0±0.1 Bq for 232Th. The detection of 238U and 232Th by FSD shows good agreement with the corresponding determination by UV–VIS spectrophotometer. The content of ThO 2 and U 3O 8 in monazite sample were found to be 4.7±0.1% and 0.42±0.04% using UV–VIS detector and 4.3±0.1% and 0.45±0.1% using FSD, respectively.

Separation and quantitative determination of dioxouranium(VI) and thorium(IV) ions in the presence of different metallic ions by TLC using iso-propyldithiophosphoric acid as complexing agent

Abstract The separation of uranium and thorium from matrices containing various metal ions, was studied. The mobile phase contains isopropyldithiophosphoric acid (i-PrDTP), as a complexing agent, in order to differentiate the studied species by modifying their retention. The paper reports the successful separation and the quantitative determination of uranium and thorium in the presence of Ni2+, Co2+ and Ag+ in the concentration range 2.5–2.5 μg/μl for uranium and 2.5–30 μg/μl for thorium.

The limit of detection improvement in TLC determination of uranium and thorium in the presence of other metal ions

The limit of detection (LOD) improvement in TLC determination of uranium and thorium in presence of other metal ions is presented in this paper. The mobile phase system contains iso-propyldithiophosphotic acid (i-PrDTP), as a complexing agent, in order to differentiate the studied species by modifying their retention. The paper reports the successful separation and the quantitative determination of uranium and thorium in the presence of other metal ions in the concentration range 2.5–30 μg/μl.

Redox determination of uranium in presence of plutonium in low phosphoric acid medium and the recovery of plutonium

Quantitative determination of uranium in (U, Pu)O2 fuels is usually done by the DAVIES-GRAY method. High concentrations of phosphoric acid in the analytical waste generated by this method make the revocery of plutonium rather complex. Studies on the recovery of plutonium from nitric acid medium containing different concentrations of H3PO4 by conventional anion-exchange procedure reveal that more than 90% of the plutonium can be easily recovered when the phosphoric acid concentration is less than 0.5 M in the solution. A method was developed for the determination of uranium in the presence of plutonium, which involves the reduction of U(VI) to U(IV) by Fe(II) in a medium of 3.5M H3PO4 +4.5M H2SO4 instead of 10–11M H3PO4 so as to have the H3PO4 concentration ∼0.6M in the waste. A number of determinations of uranium in UO2(NO3)2 working standard solutions and (U, Pu) synthetic solutions with uranium at the 3–7 mg level were carried out by this method. The precision obtained was better than ±0.2% and the accuracy was also within the precision limits. The resulting analytical waste generated was directly subjected to anion exchange separation for the recovery of plutonium which was found to be more than 90%.

The quantitative determination of uranium in human hair by fission track measurements

Abstract Human hairs containing a uranium burden were placed in contact with a mica sheet as the recording matrix and irradiated in a thermal neutron flux. The fission fragment tracks penetrating the mica were etched and counted. Calculations have been made to show the losses due to the fission fragment range being less than the diameter of the hair and for the variation of track density with distance from the line of contact between the hair and the mica. Experimental data from 50 μ. diameter hair and those derived by calculation were compared.

Field method for the estimation of uranium in natural waters

A method, applicable in the field, for the quantitative determination of uranium at the 1-ppm level in natural water has been developed. Equipment and reagents have been assembled and listed for convenience. While 1-ppm solutions have been analyzed lower concentrations can probably be evaluated in the same way.

Quantitative determination of uranium and thorium in rocks

Uranium and thorium in the parts per million range may be determined quantitatively by counting their gamma emission at 1.76 MeV and 2.62 MeV respectively. The method has been applied to natural radioactivity in silicate rock powders and other geological materials. The sensitivity and precision have been considerably increased by sample holders designed to improve the geometry of the sample in relation to the analysing crystal.

Determination of Uranium in Steel

Quantitative determination of uranium in steel heretofore has been made by precipitation of large amount of iron with ammonium carbonate or cupferron and the small amount of uranium in the filtrate is separated, but the precipitation of uranium is advantageously made by converting it into tetravalent and that of iron to divalent. The sample is treated with hydrochloric acid to give Fe2+ and U4+, the solution is neutralized with ammonium carbonate for precipitation of uranium and larger part of the iron is separated by this method. The precipitate and the insoluble residue from hydrochloric acid treatment are combined, treated with sulfuric acid and nitric acid, the solution is reprecipitated with the addition of ammonium carbonate for removal of the iron, chromium, vanadium and molybdenum etc., the filtrate is reduced with zinc amalgam and the uranium is determined by titration with potassium permanganate.

Photographie des fluoreszenzspektrums schwacher oder millimeterkleiner leuchter: Uran-nachweis mit der natriumfluoridperle, Untersuchung fluoreszierender thermalwasserabsätze und dergl

Fluorescence spectrography permits not only a qualitative determination of uranium, present in small quantities in waters of different origin or in minerals, but also a quantitative determination of uranium through photometry of the spectra. The occasional weak fluorescence or the frequently occurring minuteness of the specimens result in inconveniently long exposures with the usual spectrographs. Consequently, the author describes the construction of a miniature spectrograph which he had previously developed for use with a Contax camera and hand spectroscope for the photography of fluorescence spectra. This instrument produces good photographic spectra with superimposed wave-length scale with relatively short exposure times even in the case of samples smaller than one mm. The author discusses the manipulation of this instrument, describes exposure devices, and gives suggestions for the choice of an objective, the most suitable emulsions, development procedure, and color photographs. In his discussion of the bands characterizing the fluorescence spectrum of uranium compounds, he points out that there is a band at about 663 mμ. which has previously been overlooked on account of insufficient red sensitivity. Accordingly, the spectrum of U-NaF beads possesses seven bands.