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Rapid concentrating of radiostrontium from model fallout, drinking and technological water, using solvent extraction with cobalt dicarbollide and Slovafol 909

Journal of Radioanalytical and Nuclear Chemistry
Volume/Issue:
Volume 172: Issue 2
DOI:
https://doi.org/10.1007/bf02041840
Authors:
M. Kyrš
and
P. Selucký

Abstract  

The optimum concentration of the extractants for rapid radiostrontium concentration is 0.1M HB (chlorinated cobalt dicarbollide acid) and 1.5% vol. of Slovafol 909 in a mixture of CCl4(40%) and nitrobenzene. The recommended initial carrier concentration is 2·10–4 M Sr, initial aq. pH4.3, time of shaking 3 min. Yield in the range 80–97% can be achieved in rapidly concentrating Sr from 1 dm3 aqueous phase into 10–20 ml of the extract. The yield decreases with increasing Ca concentration in the model water. The time needed for the concentrating does not exceed 30 min.

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A rapid separation of Sr from Ca by solvent extraction with dicarbollides in the presence of EDTA and polyethylene glycols

Journal of Radioanalytical and Nuclear Chemistry
Volume/Issue:
Volume 174: Issue 1
DOI:
https://doi.org/10.1007/bf02040343
Authors:
M. Kyrš
and
P. Selucký

Abstract  

A typical composition of the solvent extraction system suitable for a rapid separation (3 min shaking) of Ca and Sr (separation factors 5000) in both tracer and macroconcentrations involves: organic phase–0.11M Li-dicarbollide and 1.65% Slovafol 909 in a mixture of 40% vol. CCl4 and 60% nitrobenzene; aqueous phase–0.15M EDTA, 0.1M (H, Li)Ac (acetate buffer), pH5.2. Replacing Slovafol 909 (suitable for the preconcentration of RdSr) by polyethylene glycol 400 enhances the distribution ratioD Sr by a factor of 7 and by a factor of 2. Using Na salts instead of Li ones IowersD Sr by a factor of 100 and does not affect the value. When separating macroamounts of Ca from Sr traces, care must be exercised to ensure the desired pH value and free EDTA concentration.

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Solvent extraction of calcium into nitrobenzene by using hydrogen dicarbollylcobaltate in the presence of dicyclohexano-18-crown-6 and dicyclohexano-24-crown-8

Journal of Radioanalytical and Nuclear Chemistry
Volume/Issue:
Volume 285: Issue 3
DOI:
https://doi.org/10.1007/s10967-010-0570-0
Authors:
E. Makrlík
,
P. Vaňura
, and
P. Selucký

Abstract  

Extraction of microamounts of calcium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B−) in the presence of dicyclohexano-18-crown-6 (DCH18C6, L) and dicyclohexano-24-crown-8 (DCH24C8, L) has been investigated. The equilibrium data have been explained assuming that the species HL+,
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $${\text{HL}}_{2}^{ + },$$ \end{document}
CaL2+ and
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $${\text{CaL}}_{2}^{2 + }$$ \end{document}
(L = DCH18C6, DCH24C8) are present in the organic phase. The values of extraction and stability constants of the complex species in nitrobenzene saturated with water have been determined. It was found that the stability constants of CaL2+ (L = DCH18C6, DCH24C8) for both ligands under study are practically the same in nitrobenzene saturated with water, whereas in this medium the stability of the complex
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $${\text{CaL}}_{2}^{2 + }$$ \end{document}
involving the DCH24C8 ligand is somewhat higher than that of
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $${\text{CaL}}_{2}^{2 + }$$ \end{document}
with the ligand DCH18C6.
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Solvent extraction of microamounts of strontium and barium into nitrobenzene by using synergistic mixture of hydrogen dicarbollylcobaltate and dicyclohexano-18-crown-6

Journal of Radioanalytical and Nuclear Chemistry
Volume/Issue:
Volume 281: Issue 3
DOI:
https://doi.org/10.1007/s10967-009-0053-3
Authors:
E. Makrlík
,
P. Vaňura
, and
P. Selucký

Abstract  

Extraction of microamounts of strontium and barium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B−) in the presence of dicyclohexano-18-crown-6 (DCH18C6, L) has been investigated. The equilibrium data have been explained assuming that the complexes HL+,
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $${\text{HL}}_{ 2}^{ + }$$ \end{document}
, ML2+ and
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $${\text{ML}}_{ 2}^{ 2+ }$$ \end{document}
(M2+ = Sr2+, Ba2+) are extracted into the organic phase. The values of extraction and stability constants of the species in nitrobenzene saturated with water have been determined. It was found that in the mentioned medium the stability constants of the complexes BaL2+ and
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $${\text{BaL}}_{2}^{2 + },$$ \end{document}
where L = DCH18C6, are somewhat higher than those of the species SrL2+ and
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $${\text{SrL}}_{2}^{2 + }$$ \end{document}
with the same ligand L.
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Solvent extraction of calcium and strontium into nitrobenzene by using hydrogen dicarbollylcobaltate in the presence of polypropylene glycol PPG 425

Journal of Radioanalytical and Nuclear Chemistry
Volume/Issue:
Volume 287: Issue 1
DOI:
https://doi.org/10.1007/s10967-010-0660-z
Authors:
E. Makrlík
,
P. Vaňura
, and
P. Selucký

Abstract  

Extraction of microamounts of calcium and strontium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B−) in the presence of polypropylene glycol PPG 425 (L) has been investigated. The equilibrium data have been explained assuming that the species HL+, CaL2+ and SrL2+ (L = PPG 425) are extracted into the organic phase. The values of extraction and stability constants of the cationic complex species in nitrobenzene saturated with water have been determined. It was found that in water-saturated nitrobenzene, the stability constant of the complex SrL2+, where L is PPG 425, is somewhat higher than that of the species CaL2+ with the same ligand L.

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Extraction of microamounts of calcium, strontium and barium into nitrobenzene by using hydrogen dicarbollylcobaltate in the presence of dibenzo-18-crown-6

Journal of Radioanalytical and Nuclear Chemistry
Volume/Issue:
Volume 277: Issue 3
DOI:
https://doi.org/10.1007/s10967-007-7115-1
Authors:
E. Makrlík
,
P. Vaňura
, and
P. Selucký

Abstract  

Extraction of microamounts of calcium, strontium and barium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B−) in the presence of dibenzo-18-crown-6 (DB18C6, L) has been investigated. The equilibrium data have been explained assuming that the complexes HL+, ML2+, ML2 2+ and MHL2 3+ (M2+ = Ca2+, Sr2+, Ba2+) are extracted into the organic phase. The values of extraction and stability constants of the species in nitrobenzene saturated with water have been determined.

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Solvent extraction of microamounts of cesium into nitrobenzene using ammonium and thallium dicarbollylcobaltates in the presence of 2,3-naphtho-15-crown-5

Journal of Radioanalytical and Nuclear Chemistry
Volume/Issue:
Volume 281: Issue 3
DOI:
https://doi.org/10.1007/s10967-009-0020-z
Authors:
E. Makrlík
,
P. Vaňura
, and
P. Selucký

Abstract  

Extraction of microamounts of cesium by a nitrobenzene solution of ammonium dicarbollylcobaltate
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$( {{\text{NH}}_{ 4}^{ + } {\text{B}}^{ - } })$$ \end{document}
and thallium dicarbollylcobaltate
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$( {{\text{Tl}}^{ + } {\text{B}}^{ - } })$$ \end{document}
in the presence of 2,3-naphtho-15-crown-5 (N15C5, L) has been investigated. The equilibrium data have been explained assuming that the complexes
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $${\text{ML}}^{ + }$$ \end{document}
and
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $${\text{ML}}_{ 2}^{ + }$$ \end{document}
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$( {{\text{M}}^{ + } = {\text{NH}}_{4}^{ + } ,{\text{Tl}}^{ + } ,{\text{Cs}}^{ + } } )$$ \end{document}
are present in the organic phase. The stability constants of the
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $${\text{ML}}^{ + }$$ \end{document}
and
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $${\text{ML}}_{2}^{ + }$$ \end{document}
species
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$( {{\text{M}}^{ + } = {\text{NH}}_{4}^{ + } ,{\text{Tl}}^{ + } })$$ \end{document}
in nitrobenzene saturated with water have been determined. It was found that the stability of the complex cations
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $${\text{ML}}^{ + }$$ \end{document}
and
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $${\text{ML}}_{2}^{ + }$$ \end{document}
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$({{\text{M}}^{ + } = {\text{NH}}_{4}^{ + } ,{\text{Tl}}^{ + } ,{\text{Cs}}^{ + } ;\;{\text{L}} = {\text{N}}15{\text{C}}5})$$ \end{document}
in the mentioned medium increases in the
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $${\text{Cs}}^{ + }\,<\, {\text{NH}}_{4}^{ + }\,<\,{\text{Tl}}^{ + }$$ \end{document}
order.
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Solvent extraction of cesium into nitrobenzene by using a synergistic mixture of hydrogen dicarbollylcobaltate and polypropylene glycol PPG 425

Journal of Radioanalytical and Nuclear Chemistry
Volume/Issue:
Volume 287: Issue 3
DOI:
https://doi.org/10.1007/s10967-010-0855-3
Authors:
E. Makrlík
,
P. Vaňura
, and
P. Selucký

Abstract  

Extraction of microamounts of cesium by a nitrobenzene solution of hydrogen dicarbollylcobaltate (H+B−) in the presence of polypropylene glycol PPG 425 (L) has been investigated. The equilibrium data have been explained assuming that the complex species HL+ and CsL+ (L = PPG 425) are extracted into the organic phase. The values of extraction and stability constants of the cationic complex species in nitrobenzene saturated with water have been determined.

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Solvent extraction of some divalent metal cations into nitrobenzene by using an anionic ligand based on cobalt bis(dicarbollide) anion with covalently bonded CMPO function

Journal of Radioanalytical and Nuclear Chemistry
Volume/Issue:
Volume 293: Issue 1
DOI:
https://doi.org/10.1007/s10967-012-1770-6
Authors:
E. Makrlík
,
P. Selucký
, and
P. Vaňura

From extraction experiments and
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\gamma$$ \end{document}
-activity measurements, the exchange extraction constants corresponding to the general equilibrium M2+(aq) + CaL2(nb)
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\Leftrightarrow$$ \end{document}
ML2(nb) + Ca2+(aq) taking place in the two–phase water–nitrobenzene system (M2+ = Mg2+, Sr2+, Ba2+, Cu2+, Zn2+, Cd2+, Pb2+,
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $${\text{UO}}_{ 2}^{ 2+ }$$ \end{document}
, Co2+, Ni2+, Mn2+;
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $${\text{L}}^{ - }$$ \end{document}
 = anionic ligand based on cobalt bis(dicarbollide) anion with covalently bonded CMPO function; aq = aqueous phase, nb = nitrobenzene phase) were evaluated. Furthermore, the stability constants of the electroneutral complex species ML2 in water-saturated nitrobenzene were calculated; they were found to increase in the following cation order: Sr2+ < Ba2+, Ni2+ < Mg2+ < Co2+ < Zn2+, Cd2+ < Mn2+ < Cu2+ < Pb2+ < 
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\text{UO}_{2}^{2 + }$$ \end{document}
.
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Extraction of cesium into phenyltrifluoromethyl sulfone by using hydrogen dicarbollylcobaltate in the presence of polyethylene glycol PEG 400

Journal of Radioanalytical and Nuclear Chemistry
Volume/Issue:
Volume 286: Issue 1
DOI:
https://doi.org/10.1007/s10967-010-0655-9
Authors:
E. Makrlík
,
P. Vaňura
, and
P. Selucký

Abstract  

Extraction of microamounts of cesium by a phenyltrifluoromethyl sulfone (FS 13) solution of hydrogen dicarbollylcobaltate (H+B−) in the presence of polyethylene glycol PEG 400 (L) has been investigated. The equilibrium data have been explained assuming that the species HL+ and CsL+ (L = PEG 400) are extracted into the organic phase. The values of extraction and stability constants of the cationic complex species in FS 13 saturated with water have been determined.

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