| Title: |
direct detection and identification of uranium(vi)-bearing solids by trlfs and chemometrics analysis |
| Authors: |
Vercouter, T.; Vors, E.; Sirven, Jb.; Lecointe, M.; Szenknect, Stephanie; Wattinne, A.; Descostes, M. |
| Contributors: |
CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)); Commissariat à l'énergie atomique et aux énergies alternatives (CEA); AREVA MINES Courbevoie |
| Source: |
Migration ; https://hal.science/hal-02418152 ; Migration, Sep 2017, Barcelone, Spain |
| Publisher Information: |
CCSD; Migration |
| Publication Year: |
2017 |
| Collection: |
HAL-CEA (Commissariat à l'énergie atomique et aux énergies alternatives) |
| Subject Terms: |
uranium; spectrofluorimetrie laser; mineraux; sites miniers; [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex]; [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th] |
| Subject Geographic: |
Spain |
| Time: |
Barcelone, Spain |
| Description: |
International audience ; Uranium can be naturally found in the environment in the form of minerals, precipitates, and/or associated to other compounds like iron (hydr)oxides or clay rocks. Identification of the nature of the uranium compounds is of major importance for geological survey, mining exploration, and management of the environmental impact of industrial sites. Many studies have been conducted to characterize uranium-bearing solids with low uranium content from ppm to hundreds of ppm. This requires a careful search of uranium-rich zones in the sample, and the use of characterization methods such as SEM, XRD, and total elemental analysis. Such a methodology is rather long and difficult, and limits the survey to a small number of samples.Time-resolved laser induced fluorescence spectroscopy (TRLFS) is a classical technique that enables the detection of U(VI) at low level, and has been largely used for quantitative and speciation analyses, in solution [1] and in minerals [2]. The rapidity of the analysis is particularly interesting to investigate a large number of samples with no or limited preparation steps, to detect traces of U(VI) and to obtain spectroscopic information that can be related to the nature of the uranium(VI)-bearing phases such as phosphates. In this study, about twenty U(VI) fluorescence spectra have been recorded on a large set of samples from several environmental sites. The fluorescence intensity is however highly variable regarding the phases due to enhancing and quenching effects on the fluorescence. Interpretation of these measurements is not straightforward. Measurements on cooled or cryogenized samples can considerably increase the fluorescence intensity and the resolution of the spectra, and help identifying the chemical family of the phases [3]. However the resulting spectral analysis is often ambiguous for phase identification and improved data treatment methods need to be developed.Chemometrics provide useful multivariate methods for spectral and classification analysis, but ... |
| Document Type: |
conference object |
| Language: |
English |
| Availability: |
https://hal.science/hal-02418152 |
| Accession Number: |
edsbas.6ADDA783 |
| Database: |
BASE |