Trace determination of uranium in fertilizer samples by total reflection X-ray fluorescence

Abstract

Uranium is reported to be present in phosphate fertilizers. The recovery of uranium from the fertilizers is important because it can be used as fuel in nuclear reactors and also because of environmental concerns. For both these activities suitable method of uranium determinations at trace levels in these fertilizers are required. Studies have been initiated for such TXRF determination of uranium and the results are reported in the present paper. For TXRF determinations the fertilizer samples were processed with nitric acid and the uranium present in it was removed by solvent extraction using tri-n-butyl phosphate as the extractant. The organic phase containing uranium was equilibrated with 1.5% suprapure nitric acid to bring out uranium in aqueous phase. This aqueous phase was mixed with internal standard Y and the TXRF spectra were measured by depositing samples on float glass supports. The amounts of uranium in four fertilizer samples of Hungarian origin were determined by processing these TXRF spectra. Uranium concentrations in two fertilizer samples were found to be in the range of 4-6 μg/g, whereas two fertilizer samples did not show the presence of uranium. The precision of the TXRF determination of uranium was found to be better than 8% (1σ ).

Recent advances in ultra‐trace determination of uranium in natural water using total reflection X‐ray fluorescence (TXRF) spectrometry

“…economically. [10][11][12] Seawater is in fact the host of many precious elements. Although the concentration of uranium in seawater is very small (3.3 ng/mL), but considering the huge volume of seawater it could act as a great reserve for uranium.…”

Atomic spectrometry update—X-ray fluorescence spectrometry

“…Since some of these materials are radioactive, a major advantage of TXRF is the small sample mass required for the analysis, hence radioactive waste of the sample and radiation exposure to the operator and the detector are minimal. The same group 118 reported the recovery of uranium from phosphor-based fertilizers for use as a fuel in nuclear reactors and to minimize the environmental pollution. For TXRF determinations, the fertilizer samples were processed with nitric acid and the uranium was removed using tri-n-butyl phosphate as the extractant.…”

Total-reflection X-ray fluorescence determination of thorium and uranium in the presence of interfering elements in solid geological objects of natural and technogenic origin

“…The rst way is the chemical separation of competing elements, as well as the preconcentration of the analytes. [30][31][32][33] Obviously, it works well for liquids, but it is a step back in the analysis of solids due to the necessity of chemical digestion. The second way of solving the problem of line overlapping for solids is to employ not the most intensive line of the (K or L) a series, but the less intensive (K or L) b-line for the analysis.…”