Influence of the extractant on strontium transport from reprocessing concentrate solutions through flat-sheet supported liquid membranes

Journal Article · Sat Oct 01 04:00:00 EDT 1994 · Separation Science and Technology

DOI:https://doi.org/10.1080/01496399408002186· OSTI ID:99109

Dozol, J F; Casas, J ^[1]; Sastre, A M ^[2]

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1. Centre d`Etudes Nucleaires de Cadarache, Saint Paul lez Durance (France)
2. Universitat Politecnica de Catalunya, Barcelona (Spain)

The influence of the extractant on strontium transport through a flat-sheet-supported liquid membrane from nuclear fuel reprocessing concentrate solutions to demineralized water has been studied using two crown ethers of different lipophilicity: dicyclohexano-18-crown-6 (DC18C6) and di-tert-butylcyclohexano-18-crown-6 (DtBuC18C6). The distribution coefficients of strontium showed that DC18C6 is a better strontium extractant than DtBuC18C6 in the entire range of crown-ether concentration studied. No effect of association between the DC18C6 molecules was observed even at high concentrations. However, the strong lipophilic character of DtBuC18C6 led to a distribution coefficient of this extractant 10 times higher than the distribution coefficient of DC18C6. Thus, the membrane concentration of DtBuC18C6 was approximately 10 times higher than that of DC18C6. This leads to greater strontium permeability for DtBuC18C6, even though DC18C6 had a greater capacity for strontium extraction and a higher diffusion coefficient in the membrane due to the smaller molar volume of this crown ether. The precipitation of a white solid was observed when the synthetic concentrate was mixed with an organic phase containing DtBuC18C6 dissolved in n-hexylbenzene (0.7 mol{center_dot}L{sup {minus}1} isotridecanol), causing a decrease of strontium permeability. In this case, DC18C6 had the greatest strontium permeability.

• Sponsoring Organization: USDOE
• OSTI ID: 99109
• Journal Information: Separation Science and Technology, Journal Name: Separation Science and Technology Journal Issue: 15 Vol. 29; ISSN 0149-6395; ISSN SSTEDS
• Country of Publication: United States
• Language: English

Related Subjects

05 NUCLEAR FUELS
CAPACITY
CROWN ETHERS
DIFFUSION
EXTRACTION
LIQUID WASTES
MEMBRANES
PERMEABILITY
PRECIPITATION
RADIOACTIVE WASTES
REPROCESSING
SPENT FUELS
STRONTIUM
SUPPORTED LIQUID MEMBRANES