001016755 001__ 1016755
001016755 005__ 20240708133945.0
001016755 037__ $$aFZJ-2023-03741
001016755 041__ $$aEnglish
001016755 1001_ $$0P:(DE-Juel1)144040$$aBrandt, Felix$$b0$$eCorresponding author$$ufzj
001016755 1112_ $$a21st Jena Remediation Symposium$$cJena$$d2023-10-04 - 2023-10-06$$wGermany
001016755 245__ $$aRetention Mechanisms for 226Ra: solid-solution formation and adsorption
001016755 260__ $$c2023
001016755 3367_ $$033$$2EndNote$$aConference Paper
001016755 3367_ $$2DataCite$$aOther
001016755 3367_ $$2BibTeX$$aINPROCEEDINGS
001016755 3367_ $$2ORCID$$aLECTURE_SPEECH
001016755 3367_ $$0PUB:(DE-HGF)31$$2PUB:(DE-HGF)$$aTalk (non-conference)$$btalk$$mtalk$$s1696850902_26498$$xInvited
001016755 3367_ $$2DINI$$aOther
001016755 520__ $$aThe fate of Ra, a decay product of 232Th, 235U, and 238U, in the environment is relevant because Ra is an important source of radioactivity in technically enhanced naturally occurring radioactive materials (TENORM). Ra-containing TENORM essentially originates from mining (e.g., uranium, phosphate) and milling operations, from coal ash, and raw material production processes e.g., oil extraction, geothermal energy production. 226Ra is a critical radionuclide in nuclear waste management, originating from e.g., nuclear industry in spent nuclear fuel or other wastes from processing uranium ore, past legacies from industry and medicine. 226Ra, is safety relevant for the deep geological disposal of spent nuclear fuel (SNF) because it is a long-lived alpha emitter (t1/2 = 1600 yrs) which dominates the radioactive dose in some scenarios regarding the late stages of SNF disposal. The prediction of 226Ra migration requires a quantitative process-understanding of the relevant retention mechanisms, i.e. adsorption, and uptake of  226Ra into a solid phase. Here we present results of experimental and theoretical studies on the structural uptake of 226Ra into the ternary solid solution of (Ba,Sr,Ra)SO4 due to the recrystallization of sulfates. This mechanism is relevant due to the fact that the solid-solutions are thermodynamically more stable than the pure phase RaSO4 and their formation leads to a lower solubility of 226Ra compared to the pure phase. The results show that already at time scales observable in the laboratory, pure sulfates are able to take up 226Ra and that their uptake can be described with thermodynamic solid-solution models. In addition, we present results regarding the adsorption of 226Ra on two important clay minerals, illite and montmorillonite. Our results show distinct differences between the selectivity of 226Ra adsorption to the two clay minerals, with a higher selectivity observed on illite. Parallel experiments with Ba indicate that 226Ra behaves similar in many geochemical conditions but is adsorbed stronger than Ba.
001016755 536__ $$0G:(DE-HGF)POF4-1411$$a1411 - Nuclear Waste Disposal (POF4-141)$$cPOF4-141$$fPOF IV$$x0
001016755 7001_ $$0P:(DE-Juel1)130364$$aKlinkenberg, Martina$$b1$$ufzj
001016755 7001_ $$0P:(DE-HGF)0$$aBaeyens, Bart$$b2
001016755 7001_ $$0P:(DE-HGF)0$$aMarquez Fernandes, Maria$$b3
001016755 7001_ $$0P:(DE-Juel1)130525$$aBarthel, Juri$$b4$$ufzj
001016755 7001_ $$0P:(DE-Juel1)130324$$aBosbach, Dirk$$b5$$ufzj
001016755 909CO $$ooai:juser.fz-juelich.de:1016755$$pVDB
001016755 9101_ $$0I:(DE-588b)5008462-8$$6P:(DE-Juel1)144040$$aForschungszentrum Jülich$$b0$$kFZJ
001016755 9101_ $$0I:(DE-588b)5008462-8$$6P:(DE-Juel1)130364$$aForschungszentrum Jülich$$b1$$kFZJ
001016755 9101_ $$0I:(DE-588b)5008462-8$$6P:(DE-Juel1)130525$$aForschungszentrum Jülich$$b4$$kFZJ
001016755 9101_ $$0I:(DE-588b)5008462-8$$6P:(DE-Juel1)130324$$aForschungszentrum Jülich$$b5$$kFZJ
001016755 9131_ $$0G:(DE-HGF)POF4-141$$1G:(DE-HGF)POF4-140$$2G:(DE-HGF)POF4-100$$3G:(DE-HGF)POF4$$4G:(DE-HGF)POF$$9G:(DE-HGF)POF4-1411$$aDE-HGF$$bForschungsbereich Energie$$lNukleare Entsorgung, Sicherheit und Strahlenforschung (NUSAFE II)$$vNukleare Entsorgung$$x0
001016755 9141_ $$y2023
001016755 9201_ $$0I:(DE-Juel1)IEK-6-20101013$$kIEK-6$$lNukleare Entsorgung$$x0
001016755 9201_ $$0I:(DE-Juel1)ER-C-2-20170209$$kER-C-2$$lMaterialwissenschaft u. Werkstofftechnik$$x1
001016755 980__ $$atalk
001016755 980__ $$aVDB
001016755 980__ $$aI:(DE-Juel1)IEK-6-20101013
001016755 980__ $$aI:(DE-Juel1)ER-C-2-20170209
001016755 980__ $$aUNRESTRICTED
001016755 981__ $$aI:(DE-Juel1)IFN-2-20101013