Chemical Separation of Uranium and Precise Measurement of 234U/238U and 235U/238U Ratios in Soil Samples Using Multi Collector Inductively Coupled Plasma Mass Spectrometry

Abstract

A new chemical separation has been developed to isolate uranium (U) using two UTEVA columns to minimize iron and thorium interferences from high background area soil samples containing minerals like monazites and ilmenite. The separation method was successfully verified in some certified reference materials (CRMs), for example, JSd-2, JLk-1, JB-1 and JB-3. The same method was applied for purification of U in Fukushima soil samples affected by the Fukushima dai-ichi nuclear power station (FDNPS) accident. Precise and accurate measurement of 234U/238U and 235U/238U isotope ratios in chemically separated U were carried out using a multi-collector inductively coupled plasma mass spectrometer (MC-ICP-MS). In this mass spectrometric method, an array of two Faraday cups (1011 Ω, 1012 Ω resistor) and a Daly detector were simultaneously employed. The precision of U isotope ratios in an in-house standard was evaluated by replicate measurement. Relative standard deviation (RSD) of 234U/238U and 235U/238U were found to be 0.094% (2σ) and 0.590% (2σ), respectively. This method has been validated using a standard reference material SRM 4350B, sediment sample. The replicate measurements of 234U/238U in SRM shows 0.7% (RSD). This developed method is suitable for separation of U and its isotope ratio measurement in environmental samples.

MIL-101 (Fe) @Ag Rapid Synergistic Antimicrobial and Biosafety Evaluation of Nanomaterials

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<p>Combining the Fibrinogen-to-Pre-Albumin Ratio and Prognostic Nutritional Index (FPR-PNI) Predicts the Survival in Elderly Gastric Cancer Patients After Gastrectomy</p>

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Atomic spectrometry update – a review of advances in environmental analysis

“…Interest in the measurement of isotope ratios has led to the development and application of new MC-ICP-MS isotope methods for the measurement of the following: 11 B/ 10 B in irrigation water and bell pepper plants to study B fractionation during uptake and translocation; 153 114 Cd/ 110 Cd in rock, soil and manganese nodule CRMs; 102 208 Pb/ 206 Pb and 207 Pb/ 206 Pb in soil and wine as a potential geographic tracer for authentication of Lambrusco PDO wines from Modena; 154 130 Te/ 126 Te in mine tailings, soil and sediment by HG-MC-ICP-MS as indicators of Te mobility and environmental redox conditions; 155 and 234 U/ 238 U and 235 U/ 238 U in soils from Odisha, India and Fukushima, Japan. 156 Although it was reported 157 that MC-ICP-MS was not necessary for measurement of 67 Zn/ 66 Zn in soil-fertiliser-plant systems as the precision obtained with standard quadrupole ICP-MS was adequate, this study featured the addition of a nutrient solution containing highly enriched 67 Zn and so did not concern the measurement of natural isotopic variations.…”