Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Dec 21:10:1085868.
doi: 10.3389/fchem.2022.1085868. eCollection 2022.

Lead-vanadate sorbents for iodine trapping and their conversion into an iodoapatite-based conditioning matrix

R Pénélope  1 , L Campayo  1 , M Fournier  1 , S Le Gallet  2 , A Gossard  3 , A Grandjean  3
Affiliations

Lead-vanadate sorbents for iodine trapping and their conversion into an iodoapatite-based conditioning matrix

R Pénélope et al. Front Chem. .

Abstract

New lead-vanadate based sorbents were synthesized with the aim to entrap and confine gaseous iodine in off-gas streams coming from reprocessing facilities of spent nuclear fuel. Their synthesis relies on the shaping of a lead-vanadate, lead sulfide and alginic acid mix as millimetric beads. These beads were calcined between 220°C and 500°C to remove organic alginic compounds template. However, according to the calcination temperature, lead sulfide could be partially oxidized, limiting iodine loading capacity. A compromise temperature between 290°C and 350°C was found to remove most of the alginic acid template and avoiding lead sulfide oxidation. These sorbents were tested for iodine trapping in static conditions at 60°C. They performed well with a sorption capacity up to 155 mg.g-1 by forming PbI2. Furthermore, these iodine-loaded sorbents could be easily converted into an iodine-containing lead-vanadate apatite matrix by spark plasma sintering. A dense sample was produced for a sintering temperature of 500°C under 70 MPa. Such a material could be suitable for radioactive iodine conditioning in deep geological disposal. Finally, lead-vanadate sorbents could provide an easy way to entrap and confine radioactive iodine from off-gas streams into a durable material within a few steps.

Keywords: apatite; filter; iodine; off-gas; waste disposal.

PubMed Disclaimer

Conflict of interest statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Figures

FIGURE 1
FIGURE 1
Pictures of the obtained beads calcined at 500°C at each step of the synthesis.
FIGURE 2
FIGURE 2
X-Ray diffractograms of (A) PbVP, PbS, lead-vanadate sorbents calcined at 220, 290, 350°C and (B) calcined at 400, 450 and 500°C.
FIGURE 3
FIGURE 3
X-Ray elemental mapping analysis of a cross-section of a sorbent bead calcined at 500°C.
FIGURE 4
FIGURE 4
Sorbents calcined at 290°C before and after exposure to I2(g).
FIGURE 5
FIGURE 5
X-Ray diffractograms of lead-vanadate sorbents calcined at different temperatures after iodine capture.
FIGURE 6
FIGURE 6
Matrix obtained after SPS conversion of iodine-loaded sorbents calcined at 350°C (A) in front view and (B) in slice view. (C) Graphite tools used after the sorbents conversion.
FIGURE 7
FIGURE 7
SEM pictures (BSE) (A) x34, (B) x200, (C) x3000 and (D) x6000 as well as EDS and elemental quantification of the matrix.
FIGURE 8
FIGURE 8
X-Ray diffractogram of the matrix.
FIGURE 9
FIGURE 9
Experimental (Rexp) and simulated (Rsimu) X-Ray diffractograms of the matrix. Bragg positions of the several phases and intensity differences between Rexp and Rsimu are also presented.
See this image and copyright information in PMC

References

    1. Abasalizadeh F., Moghaddam S. V., Alizadeh E., Akbari E., Kashani E., Fazljou S. M. B., et al. (2020). Alginate-based hydrogels as drug delivery vehicles in cancer treatment and their applications in wound dressing and 3D bioprinting. J. Biol. Eng. 14, 8. 10.1186/s13036-020-0227-7 - DOI - PMC - PubMed
    1. Audubert F. (1995). Mise au point d’une matrice apatitique pour le confinement de l’iode 129. These de doctorat. Toulouse: INPT. [Internet][cited 2022 Oct 6]. Available from: https://www.theses.fr/1995INPT001G .
    1. Audubert F., Savariault J. M., Lacout J. L. (1999). Pentalead tris(vanadate) iodide, a defect vanadinite-type compound. Acta Crystallogr. Sect. C 55 (3), 271–273. 10.1107/s0108270198005034 - DOI
    1. Azambre B., Chebbi M., Leroy O., Cantrel L. (2018). Effects of zeolitic parameters and irradiation on the retention properties of silver zeolites exposed to molecular iodine. Ind. Eng. Chem. Res. 57 (5), 1468–1479. 10.1021/acs.iecr.7b03579 - DOI
    1. Bertelsen E. R., Antonio M. R., Jensen M. P., Shafer J. C. (2022). Electrochemistry of PUREX: R is for reduction and ion transfer. Solvent Extr. Ion Exch. 40 (1–2), 64–85. 10.1080/07366299.2021.1920674 - DOI

LinkOut - more resources