2. Procedures by Element

An-1

Actinides

SEPARATION TIME: Few min

SEPARATION TECHNIQUE: Gas chromatography

PRODUCTION MODE: Autobatch

REFERENCE: Greulich, N., Hickmann, U., Trautmann, N., and Herrmann, G., “Fast preparation and gas-chromatographic separation of lanthanide and actinide hexafluoroacetylacetonates,” Z. Anal. Chem. 323, 839–845 ( 1986).

PROCEDURE: The nuclear-reaction products were loaded onto a column of Chromosorb G coated with a mixture of hexafluoroacetylacetone (HFA) and trioctylphosphine oxide (TOPO). The column containing the actinide complexes was injected into the GC. A 2-m Chromosorb G column was used. Only trivalent actinides volatilized. Americium was volatilized around 200°C. For further details, please see procedure Ln-3 under “Lanthanides,” Greulich, N., Hickmann, U., Trautmann, N., and Herrmann, G.

Ac-1

Actinium

SEPARATION TIME: 3 min

SEPARATION TECHNIQUE: Extraction

PRODUCTION MODE: Batch

REFERENCE: Chu, Y. Y., and Zhou, M. L., “Identification of 233Ac,” Phys. Rev. C 28, 1379–1381 ( 1983).

PROCEDURE: Uranium targets (50–300 mg/cm2) irradiated for 3 to 8 min with 28-GeV protons were dissolved, adjusted to 8M in HCl, and extracted with HDEHP in toluene (50%). Thorium was extracted by HDEHP, leaving actinium in the aqueous phase. Extractions were repeated to remove thorium completely. Actinium was further purified by HDEHP, TTA extractions, and anion exchange. This procedure specifically achieves separation of actinium from thorium in a short time.



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ULTRAFAST CHEMICAL SEPARATIONS 2. Procedures by Element An-1 Actinides SEPARATION TIME: Few min SEPARATION TECHNIQUE: Gas chromatography PRODUCTION MODE: Autobatch REFERENCE: Greulich, N., Hickmann, U., Trautmann, N., and Herrmann, G., “Fast preparation and gas-chromatographic separation of lanthanide and actinide hexafluoroacetylacetonates,” Z. Anal. Chem. 323, 839–845 ( 1986). PROCEDURE: The nuclear-reaction products were loaded onto a column of Chromosorb G coated with a mixture of hexafluoroacetylacetone (HFA) and trioctylphosphine oxide (TOPO). The column containing the actinide complexes was injected into the GC. A 2-m Chromosorb G column was used. Only trivalent actinides volatilized. Americium was volatilized around 200°C. For further details, please see procedure Ln-3 under “Lanthanides,” Greulich, N., Hickmann, U., Trautmann, N., and Herrmann, G. Ac-1 Actinium SEPARATION TIME: 3 min SEPARATION TECHNIQUE: Extraction PRODUCTION MODE: Batch REFERENCE: Chu, Y. Y., and Zhou, M. L., “Identification of 233Ac,” Phys. Rev. C 28, 1379–1381 ( 1983). PROCEDURE: Uranium targets (50–300 mg/cm2) irradiated for 3 to 8 min with 28-GeV protons were dissolved, adjusted to 8M in HCl, and extracted with HDEHP in toluene (50%). Thorium was extracted by HDEHP, leaving actinium in the aqueous phase. Extractions were repeated to remove thorium completely. Actinium was further purified by HDEHP, TTA extractions, and anion exchange. This procedure specifically achieves separation of actinium from thorium in a short time.

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ULTRAFAST CHEMICAL SEPARATIONS AC-2 Actinium SEPARATION TIME: 100 s SEPARATION TECHNIQUE: Extraction, ion exchange PRODUCTION MODE: Batch REFERENCE: Chayawattanangkur, K., Herrmann, G., and Trautmann, N., “Heavy isotopes of 229–232Ac,” J. Inorg. Nucl. Chem. 35, 3061–3073 ( 1973). PROCEDURE: Irradiated thorium salt was dissolved in a mixture of α-hydroxyisobutyric acid (HIB) and its ammonium salt, mixed with Dowex-50W X8 resin, and filtered. Actinium was retained by the resin along with yttrium, lanthanides, alkali, and alkaline earths. The resin was washed with NH4Cl (5%), and then with HIB (1M, pH 3.6); actinium was then eluted with HIB (1M, pH 4.65). The solution containing actinium was passed through a layer of Voltalef coated with HDEHP, which retained actinium. The Voltalef layer was washed with HCl (0.05M); actinium eluted with HCl (2M) and coprecipitated with Fe(OH)3. Sb-1 Antimony SEPARATION TIME: 2.7 s SEPARATION TECHNIQUE: Volatilization PRODUCTION MODE: Autobatch REFERENCE: Rudolph, W., Kratz, K. L., and Herrmann, G., “Half-lives, fission yields, and neutron-emission probabilities of neutron-rich antimony isotopes,” J. Inorg. Nucl. Chem. 39, 753–758 ( 1977). PROCEDURE: From the sample dissolved in HCl (12M), the hydrides of antimony, selenium, tellurium, and arsenic were volatilized by a burst of nascent hydrogen generated by the addition of zinc powder. H2Se and H2Te were absorbed on quartz wool coated with 0.5M NaOH. The gas containing AsH3 and SbH3 was passed through KClO3 – HCl (9M) solution, which decomposes the hydrides and oxidizes arsenic and antimony to (V). The solution was passed through a layer of plastic powder coated with HDEHP, which retains only antimony. Also refer to Kratz, K. L., et al., Nucl. Phys. A317, 335–362 (1979). Also see procedure Sc-1 under “Selenium,” Kratz, J. V., and Herrmann, G., J. Inorg. Nucl. Chem. 32, 3713–3723 (1970).

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ULTRAFAST CHEMICAL SEPARATIONS Sb-2 Antimony SEPARATION TIME: 5.4 s SEPARATION TECHNIQUE: Volatilization PRODUCTION MODE: Batch REFERENCE: Tomlinson, L., and Hurdus, M. H., “Delayed neutron precursors. II. Antimony and arsenic precursors separated chemically,” J. Inorg. Nucl. Chem. 30, 1649–1661 ( 1968). PROCEDURE: Uranium solution in HCl–H2SO4 containing germanium, arsenic, selenium, bromine, tin, tellurium, and iodine carriers and thiourea was used for irradiation. A stream of helium flowed through the irradiation chamber. During irradiation, hydrogen was generated by the addition of zinc. The hydrides generated, carried by the helium, were passed through a furnace maintained at a temperature below 650°C. Antimony deposited in the furnace was counted. Sb-3 Antimony SEPARATION TIME: 10 s SEPARATION TECHNIQUE: Volatilization PRODUCTION MODE: Batch REFERENCE: Greendale, A. E., and Love, D. L., “Rapid radiochemical procedure for antimony and arsenic,” Anal. Chem. 35, 632–635 ( 1963). PROCEDURE: See procedure As-5 under “Arsenic,” Greendale, A. E., and Love, D. L., Anal. Chem. 35, 632–635 (1963).

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ULTRAFAST CHEMICAL SEPARATIONS Sb-4 Antimony SEPARATION TIME: 6 s SEPARATION TECHNIQUE: Volatilization PRODUCTION MODE: Batch REFERENCE: Braun, H., Denschlag, H. O., Izak-biran, T., and Lauppe, W., “Absolute gamma-ray line intensities and branching ratios in mass chain 133,” Radiochim. Acta 36, 95–102 ( 1984). PROCEDURE: The irradiated uranium solution was mixed with HCl (12 M) and zinc powder to produce volatile hydrides of arsenic, antimony, selenium, and tellurium. The products were passed through a trap containing glass wool soaked in NaOH (0.5M); this trap retained the hydrides of selenium and tellurium. Most of the AsH3 and SbH3 passed through. A trap of glass wool coated with AgNO3 retained antimony. The gamma-ray measurements showed no interference from the decay of the isotopes of arsenic or its daughter products. Low-level contamination from tellurium was observed. Sb-5 Antimony SEPARATION TIME: 1.6 s SEPARATION TECHNIQUE: Volatilization PRODUCTION MODE: Autobatch REFERENCE: Meyer, R. A., and Henry, E. A., “Rapid, automated nuclear chemistry,” Nuclear Spectroscopy of Fission Products, T. von Egidy (Ed.) (The Institute of Physics, Bristol, 1979), p. 59–103. PROCEDURE: The fission product solution, after removal of krypton and xenon by purging with N2, was treated with sodium borohydride to produce volatile hydrides. The hydrides produced were passed through a CaSO4 trap to remove selenium and tellurium. A trap containing KOH in ethanol removed SbH3 selectively while allowing AsH3 to pass through. Also see procedure Sb-11 under “Antimony,” Hicks, H. G., et al., Phys. Rev. C 27, 2203–2216 (1983).

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ULTRAFAST CHEMICAL SEPARATIONS Sb-6 Antimony SEPARATION TIME: ~1 min SEPARATION TECHNIQUE: Extraction PRODUCTION MODE: Batch REFERENCE: Pappas, A. C., “New antimony isotopes in fission,” Phys. Rev. 81, 299A ( 1951). PROCEDURE: Irradiated uranium solution was mixed with antimony carrier and treated with Cl2 water to oxidize antimony to Sb(V). SbCl5 was extracted with isopropyl ether. The ether phase was washed with HCl – Cl2 solution. Antimony was stripped by reducing antimony to Sb(III) with N2H4 solution containing NaNCS. The aqueous solution was washed with isopropyl ether. Sb-7 Antimony SEPARATION TIME: 10 to 15 s SEPARATION TECHNIQUE: Volatilization PRODUCTION MODE: Batch REFERENCE: Troutner, D. E., Wahl, A. C., and Ferguson, R. L., “Independent fission yield of 127Sb,” Phys. Rev. 134, B1027–B1029 ( 1964). PROCEDURE: A modification of the procedure of Greendale and Love was used for the separation of antimony from fission products. Irradiated uranium solution was mixed with Sb(III) carrier in H2SO4. The resulting solution, which had 4 mg/mL of antimony and 30% H2SO4, was poured onto hot zinc granules. The SbH3 produced was swept by nitrogen gas and passed through a Br2 – HCl solution. The SbH3 was decomposed and retained by this solution. Also see procedure As-5 under “Arsenic,” Greendale, A. E., and Love, D. L., Anal. Chem. 35, 632–635 (1963). Also refer to Fowler, M. M., and Wahl, A. C., J. Inorg. Nucl. Chem. 36, 1201–1212 (1974).

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ULTRAFAST CHEMICAL SEPARATIONS Sb-8 Antimony SEPARATION TIME: ~10 s SEPARATION TECHNIQUE: Volatilization PRODUCTION MODE: Batch REFERENCE: del Marmol, P., and Néve de Mévergnies, M., “Investigation of delayed neutron precursors of As, Sb, and Ge,” J. Inorg. Nucl. Chem. 29, 273–279 ( 1967). PROCEDURE: See procedure As-8 under “Arsenic,” del Marmol, P., and Néve de Mévergnies, M., J. Inorg. Nucl. Chem. 29, 273–279 (1967). Sb-9 Antimony SEPARATION TIME: 10 to 20 s SEPARATION TECHNIQUE: Electrolysis PRODUCTION MODE: Batch REFERENCE: Tomlinson, L., and Hurdus, M. H., “Delayed neutron precursors. I. Antimony and arsenic precursors separated by electrolysis,” J. Inorg. Nucl. Chem. 30, 1125–1138 ( 1968). PROCEDURE: The hydrides of arsenic and antimony were generated in an electrolytic cell placed in the beam port of a reactor. The cell contained a solution of uranium and arsenic, germanium, tin, and antimony carriers. A current of 104 ± 4 A was passed through the cell for about 2 s, and the hydrides generated were swept by a flow of helium gas. The gases were passed through a furnace maintained at the required temperature for the selective decomposition of the hydrides. At 480°C, stibine decomposed, while a temperature of 890 °C was required for the decomposition of arsine. Tin hydride was removed when gases flowed through a CaSO4 tube before the furnace. Also see Tomlinson, L., J. Inorg. Nucl. Chem. 28, 287–301 (1966), and Anal. Chim. Acta 31, 545–551 (1964) and 32, 157–164 (1965).

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ULTRAFAST CHEMICAL SEPARATIONS Sb-10 Antimony (As) SEPARATION TIME: <10 s SEPARATION TECHNIQUE: Volatilization PRODUCTION MODE: Batch REFERENCE: Naeumann, R., Folger, H., and Denschlag, H. O., “Determination of the nuclear charge distribution in the mass 132 chain from thermal neutron fission of 235U and 233U,” J. Inorg. Nucl. Chem. 34, 1785–1797 ( 1972). PROCEDURE: See procedure Te-5 under “Tellurium,” Naeumann, R., et al., J. Inorg. Nucl. Chem. 34, 1785–1797 (1972). Sb-11 Antimony (for Te) SEPARATION TIME: 7.3 s SEPARATION TECHNIQUE: Volatilization PRODUCTION MODE: Autobatch REFERENCE: Hicks, H. G., Landrum, J. H., Henry, E. A., Meyer, R. A., Brandt, S., and Paar, V., “Population of 133I from the beta decay of fission product 133Teg and the cluster vibration model,” Phys. Rev. C 27, 2203–2216 ( 1983). PROCEDURE: Krypton and xenon were purged from a fission-product solution by a stream of N2 gas. The volatile hydrides were generated using sodium borohydride. The gas was passed through a Drierite trap to remove tellurium and tin and then through a NaOH (0.5M) trap to remove selenium. The last trap of glass wool, which was soaked in a solution of KOH in methanol, removed antimony along with arsenic. After allowing sufficient time for the decay of the required antimony isotopes, the glass wool was washed with water and mixed with a boiling solution of (NH4)2S containing tellurium and antimony carriers. Tellurium was precipitated as the element by the addition of Na2SO3. Also see procedure Sb-5 under “Antimony,” Meyer, R. A., and Henry, E. A., Nuclear Spectroscopy of Fission Products, T. von Egidy (Ed.) (The Institute of Physics, Bristol, 1979), p. 59–103.

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ULTRAFAST CHEMICAL SEPARATIONS Sb-12 Antimony SEPARATION TIME: <1 min SEPARATION TECHNIQUE: Plating, chemical PRODUCTION MODE: Batch REFERENCE: Der Mateosian, E., Goldhaber, M., Muehlause, C. O., and McKeown, M., “Multiple nuclear isomerism,” Phys. Rev. 72, 1271–1272 ( 1947). PROCEDURE: This procedure was used to confirm that the activity produced by exposure to neutrons was indeed due to an isotope of antimony. The irradiated antimony metal was dissolved in HCl. Elemental antimony was plated on iron. After removal of antimony, tin was plated out on zinc. Sb-13 Antimony SEPARATION TIME: Few s SEPARATION TECHNIQUE: Volatilization PRODUCTION MODE: Batch REFERENCE: Delucchi, A. A., Greendale, A. E., and Strom, P. O., “Cumulative fission yield and half-life of 134Sb,” Phys. Rev. 173, 1159–1165 ( 1968). PROCEDURE: Uranium solution containing Sb(III) and Mo(VI) carriers was irradiated and mixed with 30% H2SO4 (4 mL). The solution was passed through a reaction chamber containing zinc and maintained at 1300°C. The gases generated were carried by a stream of N2 through a Drierite tube and then into a hot zone in a quartz tube. The stibine decomposed and deposited antimony in the elemental form. The antimony was collected on the quartz tube and on a glass filter located downstream.

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ULTRAFAST CHEMICAL SEPARATIONS Ar-1 Argon SEPARATION TIME: <1 s SEPARATION TECHNIQUE: Condensation PRODUCTION MODE: Batch REFERENCE: Hardy, J. C., Esterl, J. E., Sexctro, R. G., and Cerny, J., “Isospin purity and delayed-proton decay: N-17 and Ar-33,” Phys. Rev. C 3, 700–718 ( 1971). PROCEDURE: Carbon disulfide vapor was irradiated with He-3 and swept with helium gas through a dry-ice trap; the carbon disulfide condensed to a liquid. The argon isotopes produced passed to the counting chamber. As-1 Arsenic SEPARATION TIME: 2.5 s SEPARATION TECHNIQUE: Volatilization PRODUCTION MODE: Autobatch REFERENCE: Kratz, J. V., Franz, H., and Herrmann, G., “Delayed neutrons from As isotopes 84As, 85As, and 86As,” J. Inorg. Nucl. Chem. 35, 1407–1417 ( 1973). PROCEDURE: Zinc powder was added to a fission product solution in HCl containing arsenic, selenium, antimony, and tellurium carriers to produce a burst of nascent hydrogen and the hydrides of the carrier elements. The hydrides were allowed to flow through a tube containing quartz wool coated with a saturated solution of KOH in ethanol; this trap removed the hydrides of selenium, antimony, and tellurium efficiently. The AsH3 flowing out of the KOH trap was decomposed in a column of firebricks coated with AgNO3. Also see Franz, H., et al., Phys. Rev. Lett. 33, 859–862 (1974). Also refer to procedure Sc-1 under “Selenium,” Kratz, J. V., and Herrmann, G., J. Inorg. Nucl. Chem. 32, 3713–3723 (1970).

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ULTRAFAST CHEMICAL SEPARATIONS AS-2 Arsenic SEPARATION TIME: 2.5 to 5 s SEPARATION TECHNIQUE: Volatilization PRODUCTION MODE: Autobatch REFERENCE: Kratz, J. V., Franz, H., and Herrmann, G., “Delayed neutrons from As isotopes 84As, 85As and 86As,” J. Inorg. Nucl. Chem. 35, 1407–1417 ( 1973). PROCEDURE: The fission product solution in HCl, containing arsenic, selenium, antimony, and tellurium carriers, was mixed with zinc powder to generate hydrides of the carrier elements. The gases generated were passed through a tube containing quartz wool coated with a saturated solution of KOH in ethanol; this trap retained the hydrides of selenium, antimony, and tellurium while AsH3 passed through. AsH3 was decomposed by passing it through a solution of KClO3 in HCl (9M); the solution was then filtered through a layer of inert plastic powder coated with HDEHP, which retained germanium, bromine, antimony, and iodine contaminants. The arsenic in the filtrate was counted. Also see Kratz, J. V., and Herrmann, G., Proceedings of the 3rd Symposium on the Physics and Chemistry of Fission, IAEA publication, Vol. 2 (Rochester, 1973), p. 95; Kratz, J. V., et al., Nucl. Phys. A250, 13–37 (1973); and Franz, H., et al., Phys. Rev. Lett. 33, 859–862 (1974). As-3 Arsenic SEPARATION TIME: 5.4 s SEPARATION TECHNIQUE: Volatilization PRODUCTION MODE: Batch REFERENCE: Tomlinson, L., and Hurdus, M. H., “Delayed neutron precursors. II. Antimony and arsenic precursors separated chemically,” J. Inorg. Nucl. Chem. 30, 1649–1661 ( 1968). PROCEDURE: Uranium solution in HCl – H2SO4 containing germanium, arsenic, selenium, bromine, tin, antimony, tellurium, and iodine carriers and thiourea was irradiated. A flow of helium was maintained through the irradiation vessel. During irradiation, the hydrides were generated by the addition of zinc to the irradiation solution. The hydrides, carried by the helium, were passed through a furnace maintained at 620°C to remove antimony. Particulate antimony was removed by a silica-wool trap. Arsenic was decomposed by a second furnace at 950°C.

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ULTRAFAST CHEMICAL SEPARATIONS As-4 Arsenic SEPARATION TIME: Few s SEPARATION TECHNIQUE: Extraction, adsorption PRODUCTION MODE: Continuous REFERENCE: Zendel, M., Trautmann, N., and Herrmann, G., “Chemical reactions in a gas-jet recoil-transport system (II): continuous separation procedures for germanium and arsenic from fission products, ” Radiochim. Acta 29, 17–20 ( 1981). PROCEDURE: Recoiling fission fragments were thermalized and carried by a stream of HCl – N2 (1 to 20, respectively). The gas was passed through a quartz-wool trap, which retained the fission products carried by clusters. The gas was then passed through a quartz spiral coated inside with silver and kept at ~800°C. The halogens formed nonvolatile products with silver and were retained in the spiral. The gas was then passed through a trap filled with polystyrene beads saturated with HDEHP, which retained arsenic almost quantitatively. Germanium in the gas coming out of the polystyrene trap was adsorbed by charcoal. The detector was set to measure the activities of the polystyrene-HDEHP trap. As-5 Arsenic SEPARATION TIME: 10 s SEPARATION TECHNIQUE: Volatilization PRODUCTION MODE: Batch REFERENCE: Greendale, A. E., and Love, D. L., “Rapid radiochemical procedure for antimony and arsenic,” Anal. Chem. 35, 632–635 ( 1963). PROCEDURE: Mixed fission-product solution in 30% H2SO4, containing arsenic and antimony carriers, was dropped onto zinc powder (10–20 mesh) kept at 100°C. The hydrides generated were passed through a Drierite tube and then passed through a furnace at 600°C. Antimony hydride decomposed at this temperature, and metallic antimony was retained by a sintered-glass filter located outside the furnace. The gas flowing through the filter was passed through a quartz tube heated to a reddish glow. Arsenic hydride decomposed at this temperature and deposited as elemental As in the cooler portions of the tube.

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ULTRAFAST CHEMICAL SEPARATIONS Y-5 Yttrium SEPARATION TIME: 40 s SEPARATION TECHNIQUE: Precipitation PRODUCTION MODE: Batch REFERENCE: Vallis, D. G., and Perkin, J. L., “Yttrium-96 and strontium-93: new nuclear data,” J. Inorg. Nucl. Chem. 22, 1–5 ( 1961). PROCEDURE: The irradiated zirconium solution was mixed with yttrium (2 mg) and strontium (50 mg) carriers in 0.5 mL of 6M HNO3 kept in the centrifuge cup of the automatic chemistry apparatus. YF3 was precipitated by the addition of a solution of 12% NH4F (1 mL); centrifugation removed the supernatant liquid automatically. The precipitate was washed once with 0.5% NH4F (2 mL) and thrice with water (2 mL). The washes removed SrF2. The YF3 was dissolved in 6M HCl saturated with boric acid and transferred for counting. Y-6 Yttrium SEPARATION TIME: Few min SEPARATION TECHNIQUE: Precipitation PRODUCTION MODE: Batch REFERENCE: Yu, Y. W., and Caretto, Jr., A. A., “The half-lives of 84Zr and 85Zr,” J. Inorg. Nucl. Chem. 33, 3223–3225 ( 1971). PROCEDURE: This procedure was used to milk yttrium daughter product from the zirconium parent. The irradiated ZrO2 was dissolved in hot 17M HF. To the solution containing zirconium, yttrium solution (5 mg in 0.5 mL) was added; the YF3 precipitate was centrifuged and removed. The YF3 scavenging was repeated three times. Periodically, the yttrium daughter growing in the zirconium solution was removed as YF3. The YF3 precipitate was centrifuged, dissolved in 8M HCl containing a few drops of HNO3, passed through a column of Dowex-1 X10, and the yttrium was eluted with 8M HCl. The yttrium was finally precipitated as oxalate, filtered, and used for counting.

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ULTRAFAST CHEMICAL SEPARATIONS Y-7 Yttrium SEPARATION TIME: Few min SEPARATION TECHNIQUE: Ion exchange PRODUCTION MODE: Batch REFERENCE: Butement, F. D. S., and Briscoe, G. B., “Neutron-deficient isotopes of yttrium and zirconium,” J. Inorg. Nucl. Chem. 25, 151–157 ( 1963). PROCEDURE: This procedure was used for milking the yttrium daughter activities from the parent zirconium. The irradiated Y2O3 sample was dissolved, and the zirconium activities were extracted using 0.5M 2-thenoyltrifluoroacetone in xylene (procedure of F. L. Moore, Anal. Chem. 28, 997, 1956 ). The zirconium was back-extracted with 2 mL of concentrated HCl; the solution was passed through a Dowex-1 column, which retained the zirconium. Yttrium daughter activities were removed periodically by washing the column with concentrated HCl. 104-1 Z = 104 SEPARATION TIME: 2 to 3 min SEPARATION TECHNIQUE: Extraction PRODUCTION MODE: Autobatch REFERENCE: Hulet, E. K., Lougheed, R. W., Wild, J. F., Landrum, J. H., Nitschke, J. M., and Ghiorso, A., “Chloride complexation of element 104,” J. Inorg. Nucl. Chem. 42, 79–82 ( 1980). PROCEDURE: Recoil products produced in the reaction 248Cm(18O,5n) were transported by a NaCl – helium gas jet and deposited on the end surface of a rabbit. The products were dissolved in the chemistry apparatus and passed through a column of fluorocarbon coated with trisoctylmethylammonium chloride dissolved in o-xylene (0.25M). Element 104 was eluted with HCl (6M).

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ULTRAFAST CHEMICAL SEPARATIONS 104-2 Z = 104 SEPARATION TIME: ∼0.4 s SEPARATION TECHNIQUE: Thermochromatography PRODUCTION MODE: Continuous REFERENCE: Zvara, I., Belov, V. Z., Chelnokov, L. P., Domanov, V. P., Hussonois, M., Korotkin, Yu. S., Schegolev, V. A., and Shalayevsky, M. R., “Chemical separation of kurchatovium,” Inorg. Nucl. Chem. Lett. 7, 1109–1116 ( 1971). PROCEDURE: Recoiling nuclear reaction products were carried by flowing nitrogen gas and mixed with chlorinating agents SOC12 and TiCl4 vapor. The mixture was passed through a 200-cm-long glass column. The first ~125 cm was maintained at 400 ± 5°C and in the rest of the column (125 to 200 cm), the thermochromatographic section, the temperature was gradually dropped from 400 to 50°C. Experiments with hafnium activity showed that hafnium deposited in this region, and that it takes ~0.4 s for hafnium to reach the deposition zone from the production region. Element 104, ekahafnium, is expected to deposit in this region. Evidence for a spontaneously fissioning isotope of Z = 104 with a mass of 259 was obtained using this procedure. Also see Zvara, I., et al., Soviet Radiochem. (Eng. Tr.) 14, 115–118 (1972). 104-3 Z = 104 SEPARATION TIME: <1 s SEPARATION TECHNIQUE: Volatilization PRODUCTION MODE: Continuous REFERENCE: Zvara, I., Chuburkov, Yu. T., Tsaletka, R., Zvarova, T. S., Shalaevskii, M. R., and Shilov, B. V., “Chemical properties of element 104,” Sov. J. At. Energy 21, 709–710 ( 1966). PROCEDURE: The recoiling reaction products were chlorinated by reaction with NbCl5 or ZrCl4 in the vapor phase. The chlorides of group III elements were deposited on the walls of the gas-flow tube or adsorbed on the special filters. The activities of element 104 were carried by the gas flow to the detector. Also see procedure 104-2 under “Z = 104,” Zvara, I., et al., Inorg. Nucl. Chem. Lett. 7, 1109–1116 (1971).

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ULTRAFAST CHEMICAL SEPARATIONS 104-4 Z = 104 SEPARATION TIME: 1 min SEPARATION TECHNIQUE: Ion exchange PRODUCTION MODE: Batch REFERENCE: Silva, R., Harris, J., Nurmia, M., Eskola, K., and Ghiorso, A., “Chemical separation of rutherfordium,” Inorg. Nucl. Chem. Lett. 6, 871–877 ( 1970). PROCEDURE: The recoiling products were collected on a platinum foil coated with NH4Cl. The products were dissolved in a small volume (~50 µL) of ammonium α-hydroxyisobutyrate (0.1M, pH 4.0). The solution was loaded on to a column of Dowex-50 X12 (2-mm diameter by 2 cm long) kept at ~80°C. The column was eluted with ammonium α-hydroxyisobutyrate. Drops number 3 to 6 were collected, evaporated to dryness, and heated to ~500°C. The sample was transferred to a counter. 105-1 Z = 105 SEPARATION TIME: 0.1 to 0.2 s SEPARATION TECHNIQUE: Thermochromatography PRODUCTION MODE: Continuous REFERENCE: Zvara, I., Belov, V. Z., Domanov, V. P., and Shalaevskii, M. R., “Chemical isolation of nilsbohrium as ekatantalum in the form of the anhydrous bromide. II. Experiments with a spontaneously fissioning isotope of nilsbohrium,” Soviet Radiochemistry (Eng. Tr.) 18, 328–334 ( 1976). PROCEDURE: Recoiling nuclear reaction products were slowed in a nickel chamber through which helium carrier gas containing Br2 and BBr3 vapor flowed continuously. The carrier gas containing the reaction products was passed through a thermochromatographic column, where the temperature dropped from 250°C to 25°C over a distance of 150 cm. Nilsbohrium bromide, less volatile than its homologs niobium and tantalum, deposited in a higher-temperature region of the column. The tracks on mica detectors located at the deposition position provided evidence for element 105. The time, taken from the formation to the deposition, was measured with radioactive niobium serving as a fiducial.

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ULTRAFAST CHEMICAL SEPARATIONS 105-2 Z = 105 SEPARATION TIME: 12 s SEPARATION TECHNIQUE: Thermochromatography PRODUCTION MODE: Continuous REFERENCE: Nai-Qi, Ya., Jost, D. T., Baltensperger, U., and Gäggeler, H. W., “The Saphir gas-jet and a first application to an on-line separation of niobium,” Radiochim. Acta 47, 1–7 ( 1989). PROCEDURE: See procedure Nb-9 under “Niobium,” Nai-Qi, Ya., Jost, D. T., Baltensperger, U., and Gäggeler, H. W., Radiochim. Acta 47, 1–7 (1989). 105-3 Z = 105 SEPARATION TIME: 55 s SEPARATION TECHNIQUE: Extraction (HPLC) PRODUCTION MODE: Autobatch REFERENCE: Kratz, J.W., Zimmermann, H.P., Scherer, U.W., Schädel, M., Brüchle, W., Gregorich, K.E., Gannett, C.M., Hall, H.L., Henderson, R.A., Lee, D.M., Leyba, J.D., Nurmia, M.J., Hoffman, D.C., Gäggeler, H., Jost, D., Baltensperger, U., Ya Nai-Qi, Fürler, A., Lienert, Ch., “Chemical properties of element 105 in aqueous solution: halide complex formation and anion exchange into triisooctyl amine,” Radiochim Acta 48, 121-133 ( 1989). PROCEDURE: Element 105 (A=262), produced by 249Bk(18O,5n) reaction, was carried by He/KCl gas jet and deposited on a polyethylene frit. After one minute of collection the jet was directed to a second frit; the first frit was moved to a position on top of an extraction column containing Voltalef (inert support) coated with triisooctyl amine (TIOA). The reaction products deposited on the frit were dissolved in 12 M HCl - 0.02 M HF and the solution passed through the column. The amine extracted halide complexes of Nb, Ta, Pa, and other transplutonium elements while other elements passed through. The column was washed with 4M HCl - 0.02 HF for ten seconds; the effluent (Pa, Nb fraction) was collected on a Ta disk and evaporated to dryness. The column was then washed with 6 M HNO3-0.015 M HF for ten seconds and the effluent (Ta fraction) was collected and evaporated to dryness. Counting of the samples started 55 s after the end of collection on the frit. In an 8-hour shift 300 separations were carried out.

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ULTRAFAST CHEMICAL SEPARATIONS 107-1 Z = 107 SEPARATION TIME: <3 s SEPARATION TECHNIQUE: Thermochromatography PRODUCTION MODE: Continuous REFERENCE: Domanov, V. P., Khyubener, Z., Shalaevskii, M. R., Timokhin, S. N., Petrov, D. V., and Zvara, I., “Experimental approach to the identification of element 107 as ekarhenium. I. Continuous gas-thermochromatographic isolation of radiorhenium, ” Soviet Radiochemistry (Eng. Tr.) 25, 23–28 ( 1983). PROCEDURE: Pure air containing water vapor at a pressure of 600 Pa (corresponding to saturated water vapor pressure at 0°C) was used as carrier gas. The recoiling nuclear reaction products were stopped in a quartz filter kept at 900°C. The carrier gas passed through a quartz thermochromatographic column with an initial temperature of 400°C and a temperature gradient of 3.5°C/cm. Under these conditions, rhenium, the homolog of element 107, was adsorbed in a temperature zone of 100 ± 20°C. Element 107, if formed, should also deposit in this zone. Track detectors kept at this position can provide evidence for spontaneous fission events from element 107. Also see Zvara, I., et al., Soviet Radiochemistry (Eng. Tr.) 26, 72–76 (1984).113,114-1 113,114-1 Z = 113,114 SEPARATION TIME: <1 min SEPARATION TECHNIQUE: Extraction PRODUCTION MODE: Continuous/batch REFERENCE: Langrock, L. J., Bazarkina, T. V., and Czosnowska, W., “Procedures for selective solvent extraction of superheavy elements 113+ and 1142+ by use of crown ethers,” Radiochim. Acta 30, 229–231 ( 1982). PROCEDURE: A possible rapid-separation procedure has been developed for Z = 113 and Z = 114 based on their predicted ionic radii. The extraction of Pb2+ and Ba2+ was studied since their ionic radii are very close to the predicted values for 113+ and 1142+. The ions were taken in an aqueous solution buffered at a pH of 4.6 and contained sodium picrate (0.02M). The ions Pb2+ and Ba2+ were extracted with ~100% efficiency by 18-crown-6-ether in CHCl 3. Lanthanides and actinides were not extracted. The ions can be stripped with HCl (6M). This procedure can be adapted for continuous on-line separation.

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ULTRAFAST CHEMICAL SEPARATIONS 118-1 Z = 118 (112 and 114 ) SEPARATION TIME: Few s SEPARATION TECHNIQUE: Condensation PRODUCTION MODE: Continuous REFERENCE: Hildebrand, N., Frink, C., Greulich, N., Hickmann, U., Kratz, J. V., Trautmann, N., Herrmann, G., Brügger, M., Gäggeler, H., Summerer, K., and Wirth, G., “A cryosystem for the detection of alpha and spontaneous-fission activities in volatile species,” Nucl. Instr. Meth. Phys. Res. A 260, 407–412 ( 1987). PROCEDURE: Recoiling nuclear-reaction products (48Ca bombardment of 248Cm or 238U bombardment of 238U) were thermalized and carried by argon gas. The gas was allowed to flow through a quartz tube filled with quartz powder and kept at 1250 K. Nonvolatile products were deposited in the tube, and clusters were destroyed. The gas then flowed through a quartz tube filled with tantalum chips maintained at 1000 K; this removed H2O, CO2 and O2 from the gas. The gas was then led into the cryogenic unit kept at 40 K. Volatile species condensed on top of a solar cell. Surface barrier detectors were used to record alpha spectra. The system was tested with short-lived radon isotopes. Zn-1 Zinc SEPARATION TIME: ∼1 s SEPARATION TECHNIQUE: Thermochromatography PRODUCTION MODE: Continuous REFERENCE: Rudstam, G., Aagaard, P., Hoff, P., Johansson, B., and Zwicky, H. O., “Chemical separation combined with an ISOL-system,” Nucl. Instr. Methods 186, 365–379 ( 1981). PROCEDURE: See procedure Cd-1 under “Cadmium,” Rudstam, G., et al., Nucl. Instr. Methods 186, 365–379 (1981).

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ULTRAFAST CHEMICAL SEPARATIONS Zn-2 Zinc SEPARATION TIME: Few min SEPARATION TECHNIQUE: Ion exchange PRODUCTION MODE: Batch REFERENCE: Cumming, J. B., “A new zinc isotope, 61Zn,” Phys. Rev. 99, 1645A ( 1955). PROCEDURE: Zinc was separated from gallium, copper, nickel, cobalt, iron, and manganese by anion exchange. The zinc fraction showed the presence of 61Cu, daughter of 1.5-min 61Zn. Conditions of the separation were not given. Zn-3 Zinc SEPARATION TIME: ∼1 min SEPARATION TECHNIQUE: Extraction PRODUCTION MODE: Batch REFERENCE: Lindner, L., and Brinkman, G. A., “60Zn and 61Zn,” Physica 21, 747–748 ( 1955). PROCEDURE: Irradiated nickel was dissolved in HNO3. Zinc di-beta-naphthylthio-carbazone was extracted into CHCl3. The extraction separated zinc from copper, nickel, cobalt and iron.

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ULTRAFAST CHEMICAL SEPARATIONS Zn-4 Zinc SEPARATION TIME: 1 to 2 min SEPARATION TECHNIQUE: Ion exchange PRODUCTION MODE: Batch REFERENCE: Hoffman, E. J., and Sarantities, D. G., “Decay schemes of 60Zn and 62Zn,” Phys. Rev. 177, 1640–1647 ( 1969). PROCEDURE: Irradiated nickel foil was dissolved in hot, concentrated HNO3. The solution was heated with concentrated HCl to eliminate HNO3 and was adjusted to be 1M in HCl. Zn2+ and Cu2+ carriers were added (0.05 mg each) to the solution and mixed, then a few mg of Dowex-1 resin was added, stirred, and filtered. The resin was washed with 1M HCl and mounted for counting. Also see Cumming, J. B., Phys. Rev. 114, 1600–1604 (1959). Zr-1 Zirconium SEPARATION TIME: 2.2 s SEPARATION TECHNIQUE: Extraction PRODUCTION MODE: Autobatch REFERENCE: Weis, M., and Densclag, H. O., “Fractional independent yields of 99Y, 99Zr, 99mNb, and 99Nb in the thermal neutron induced fission of 235U,” J. Inorg. Nucl. Chem. 43, 437–444 ( 1981). PROCEDURE: Fission product solution in HNO3 containing molybdenum and antimony carriers and tartaric acid was filtered through a preformed AgCl layer. The filtrate was made 7.5 M in HNO3 and passed through a layer of Voltalef 300 LD-PL micropowder coated with tri-n-butyl phosphoric acid. This layer retained zirconium.

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ULTRAFAST CHEMICAL SEPARATIONS Zr-2 Zirconium SEPARATION TIME: ∼7 s SEPARATION TECHNIQUE: Extraction PRODUCTION MODE: Continuous REFERENCE: Brodén, K., Skarnemark, G., Björnstad, T., Eriksen, T., Haldorsen, I., Kaffrell, N., Stender, E., and Trautmann, N., “Rapid continuous separation procedures for zirconium, niobium, technetium, bromine, and iodine from complex reaction-product mixtures,” J. Inorg. Nucl. Chem. 43, 765–771 ( 1981). PROCEDURE: Recoiling fission products, thermalized and carried by KCl aerosol, were dissolved in H2SO4 (1M), degassed at 70°C, and transferred to the first centrifuge of a SISAK-2 system. The solution was contacted with Alamine-336 (0.1M) in Shellsol-T containing n-dodecanol (5%), which extracted zirconium, niobium, technetium, and some other elements. In the second centrifuge, zirconium and niobium were stripped by HNO3 (0.3M), leaving contaminants in the organic phase. The aqueous phase was made 3M in HNO3 and 1M in H2O2. Then, zirconium was extracted with HDEHP (1M) in Shellsol-T in the third centrifuge. Zirconium was counted in the organic phase. After one more extraction for zirconium, the niobium in the aqueous phase was counted. Zr-3 Zirconium SEPARATION TIME: 4.0 s SEPARATION TECHNIQUE: Extraction PRODUCTION MODE: Autobatch REFERENCE: Trautmann, N., Kaffrell, N., Behlich, H. W., Folger, H., Herrmann, G., Hubscher, D., and Ahrens, H., “Identification of short-lived isotopes of zirconium, niobium, molybdenum, and technetium by rapid solvent-extraction technique,” Radiochim. Acta 18, 86–101 ( 1972). PROCEDURE: Irradiated uranium solution in HNO3 (0.5M), containing SO2 and tartaric acid, was passed through two layers of preformed AgCl. The filtrate was collected in concentrated HNO3 containing KClO3. The resulting solution, which was 7.5M in HNO3, was filtered through a layer of Voltalef 300 LD-PL micropowder coated with tri-n-butyl phosphoric acid. Zirconium retained by this layer was washed with HNO3 (7.5M) containing KClO3 and transported for counting.

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ULTRAFAST CHEMICAL SEPARATIONS Zr-4 Zirconium SEPARATION TIME: <3 min SEPARATION TECHNIQUE: Thermocromatography PRODUCTION MODE: Batch REFERENCE: Bayer, B., Vocilka, I., Zaitseva, N. G., and Novgorodov, A. F., "Fast gas-thermochromatographic separation of radioactive elements. IV. Extraction of neutron-deficient zirconium and niobium isotopes from irradiated silver chloride melt," Radiochem. Radioanal. Lett. 34, 63-74 (1978). PROCEDURE: Irradiated AgCl was heated to 800°C to 900°C in a stream of dry HCl gas. The gas passed through a quartz thermochromatographic column wth a negative temperature gradient. Zirconium deposited in the temperature region that corresponded to the boiling point of NbCl5 (246°C). Increasing the evporation time moved the zirconium and niobium regions close to each other. Heating in an additional O2 stream (following HCl) fixed the zirconium and niobium in nonoverlapping regions, zirconium in the temperature zone 420 ± 40°C and niobium in 230 ± 30°C. Also see Bayer, B., et al., Soviet radiochemistry (Eng. Tr.) 16, 345-351 (1974). Zr-5 Zirconium SEPARATION TIME: Few min SEPARATION TECHNIQUE: Precipitation PRODUCTION MODE: Batch REFERENCE: Dubridge, L. A., and Marshall, J., "Radioactive isotopes of strontium, yttrium, and zirconium," Phys. Rev. 58, 7-11 (1940). PROCEDURE: The irradiated YCl3 was dissolved in HNO3, and zirconium carrier was added to the solution. Zirconium was precipitated as the iodate.