Geochemical evidence for the application of nanoparticulate colloidal silica gel for in situ containment of legacy nuclear wastes

Simple item page
dc.contributor.authorLunn, RJen_AU
dc.contributor.authorBots, Pen_AU
dc.contributor.authorRenshaw, JCen_AU
dc.contributor.authorPayne, TEen_AU
dc.contributor.authorComarmond, MJen_AU
dc.contributor.authorSchellenger, AEPen_AU
dc.contributor.authorPedrotti, Men_AU
dc.contributor.authorCalì, Een_AU
dc.date.accessioned2024-09-24T05:40:59Zen_AU
dc.date.available2024-09-24T05:40:59Zen_AU
dc.date.issued2020-03-30en_AU
dc.date.statistics2024-05-09en_AU
dc.description.abstractColloidal silica is a nanoparticulate material that could have a transformative effect on environmental risk management at nuclear legacy sites through their use in in situ installation of injectable hydraulic barriers. In order to utilize such nanoparticulate material as a barrier, we require detailed understanding of its impact on the geochemistry of radionuclides in the environment (e.g. fission products such as Sr and Cs). Here we show, through combining leaching experiments with XAS analyses, that colloidal silica induces several competing effects on the mobility of Sr and Cs. First, cations within the colloidal silica gel compete with Sr and Cs for surface complexation sites. Second, an increased number of surface complexation sites is provided by the silica nanoparticles and finally, the elevated pH within the colloidal silica increases the surface complexation to clay minerals and the silica nanoparticles. XAS analyses show that Sr and Cs complex predominantly with the clay mineral phases in the soil through inner-sphere surface complexes (Sr) and through complexation on the clay basal surfaces at Si vacancy sites (Cs). For binary soil – colloidal silica gel systems, a fraction of the Sr and Cs complexes with the amorphous silica-like surfaces through the formation of outer-sphere surface complexes. Importantly, the net effect of nanoparticulate colloidal silica gel is to increase the retention of Sr and Cs, when compared to untreated soil and waste materials. Our research opens the door to applications of colloidal silica gel to form barriers within risk management strategies at legacy nuclear sites. © Royal Society of Chemistry 2024.en_AU
dc.identifier.citationBots, P., Renshaw, J. C., Payne, T. E., Comarmond, M. J., Schellenger, A. E. P., Pedrotti, M., Calì, E., & Lunn, R. J. (2020). Geochemical evidence for the application of nanoparticulate colloidal silica gel for in situ containment of legacy nuclear wastes. Environmental science: nano, 7(5), 1481-1495. doi:10.1039/D0EN00046Aen_AU
dc.identifier.issn2051-8153en_AU
dc.identifier.issn2051-8161en_AU
dc.identifier.issue5en_AU
dc.identifier.journaltitleEnvironmental science: nanoen_AU
dc.identifier.pagination1481-1495en_AU
dc.identifier.urihttps://doi.org/10.1039/d0en00046aen_AU
dc.identifier.urihttps://apo.ansto.gov.au/handle/10238/15699en_AU
dc.identifier.volume7en_AU
dc.languageEnglishen_AU
dc.language.isoenen_AU
dc.publisherRoyal Rociety of Chemistry (RSC)en_AU
dc.subjectSilica Gelen_AU
dc.subjectGeochemistryen_AU
dc.subjectGeochemical surveysen_AU
dc.subjectRadioactive wastesen_AU
dc.subjectContainmenten_AU
dc.subjectColloidsen_AU
dc.subjectEnvironmental impactsen_AU
dc.subjectRisk assessmenten_AU
dc.titleGeochemical evidence for the application of nanoparticulate colloidal silica gel for in situ containment of legacy nuclear wastesen_AU
dc.typeJournal Articleen_AU
Files
License bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
license.txt
Size:
1.66 KB
Format:
Plain Text
Description:
Download
Collections
Journal Articles