Extractants dicarbollides

Rais, J., Griiner, B. 2004. Extraction with metal bis(dicarbollide) anions Metal bis(dicarbollide) extractants and their applications in separation chemistry. In Ion Exchange and Solvent Extraction, A Series of Advances Vol. 17. Marcus, Y., SenGupta, A.K., Marinsky, J.A. Eds. Marcel Dekker, New York, pp. 243-334. 

EXTRACTION WITH METAL BIS(DICARBOLLIDE) ANIONS METAL BIS(DICARBOLLIDE) EXTRACTANTS AND THEIR APPLICATIONS IN SEPARATION CHEMISTRY ]iH Rais and Bohumir Griiner... 

Cobalt bis(dicarbollide) Extractants with Covalently Attached Selective Groups.472... 

COBALT BIS(DICARBOLLIDE) EXTRACTANTS WITH COVALENTLY ATTACHED SELECTIVE GROUPS... 

Kyrs, M. 1994. 23 Years of dicarbollide extraction of metals research and applications. J. Radioanal. Nucl. Chem. Lett. 187 185-195. 

Alyapyshev, M.Yu., Babain, V.A., Smirnov, I.V. 2004. Extractive properties of synergistic mixtures of dipicolinic acid diamides and chlorinated cobalt dicarbollide. Radiochemistry 46 (3) 270-271. 

Rais, J.,Tachimori, S. 1994. Extraction separation of tervalent americium and lanthanides in the presence of some soft and hard donors and dicarbollide. Sep. Sci. Technol. 29 (10) 1347-1365. 

Dozol, J.F., Dozol, M., Macias, R.M. 2000. Extraction of strontium and cesium by dicarbollides, crown ethers and functionalized calixarenes. J. Incl. Phenom. Macrocycl. Chem. 38 (1-4) 1-22. 

Miller, R.L., Pinkerton, A.B., Hurlburt, P.K., Abney, K.D. 1995. Extraction of cesium and strontium into hydrocarbon solvents using tetra-C-alkyl cobalt dicarbollide. Solvent Extr. IonExch, 13 (5) 831-827. 

Law, J.D., Herbst, R.S., Peterman, D.R. et al. 2005. Development of aregenerable strip reagent for treatment of acidic, radioactive waste with cobalt dicarbollide based solvent extraction processes. Solvent Extr. Ion Exch. 23 (1) 59-84. 

Griiner, B., Plesek, J., Baca, J. et al. 2002. Crown ether substituted cobalt bis(dicarbollide) ions as selective extraction agents for removal of Cs + and Sr2 + from nuclear waste. New J. Chem. 26 (7) 867-875. 

Todd, T.A., Brewer, K.N., Law, J.D., Herbst, R.S., Wood, D.J., Romanovskiy, V.N., Esimantovskiy, V.N., Smirnov, I.V., Babain, V.A., Zaitsev, B. 1999. Development of a universal cobalt dicarbollide solvent for the removal of actinides, cesium and strontium from acidic wastes. ISEC 99 Conference on Solvent Extraction for the 21st Century, July, Barcelona, Spain. 

Tetraphenylborate (TPB) was used at Savannah River to recover cesium from alkaline solutions, but attempts to treat HLW tanks with TPB resulted in the production of benzene (a TPB decomposition product) at levels that did not permit the safe operation of the process.8 Crown ethers and dicarbollides were proposed as extractants to remove cesium from acidic HAW, but these compounds are not selective enough to allow cesium to be removed from solutions containing large amounts of nitric acid or sodium nitrate.9 Dicarbollides were used in Russia at industrial scale to recover cesium from HAW, but the removal of cesium was only possible after partial denitration of the liquid waste.10... 

In the second project, gathering nine teams from six EC countries, more than 150 new extractants were prepared and studied, and the target was reached for the decategorization of waste. Dialkoxy calix[4]arene-crown-6 for cesium, octaamide calix[8] arenes, and CMPO-like calixarenes for actinides display much higher complexing and extracting abilities than other classical extractants, crown ethers, or dicarbollides proposed and sometimes used for this purpose. 

Most of the studies carried out on cesium extraction conclude that the most efficient crown ethers for extraction of this cation are benzo-21-crown-7 derivatives. Like dicarbollides, these compounds need a synergistic agent or polar diluent modifier to allow cesium to be extracted from very acidic solutions. The resulting selectivity for cesium over sodium is low. Only dialkoxy-calix[4]arene-crown-6 and calix[4]arene bis(crown-6) compounds allow objectives to be fulfilled extraction of cesium at low-level concentration from acidic media.19... 

Previously, we saw that the extractants used for the extraction of strontium were DC18C6 derivatives or dicarbollide derivatives. Strontium can be effectively extracted with a synergistic mixture of dicarbollide and polyethylene glycols or crown ethers. A drawback of this process is the use of high-polarity diluents, such as nitrobenzene or chlorinated compounds, in order to solubilize the mixture of the extractants.127... 

In mixtures with the hydrophobic dicarbollide anion, the extraction of Ca, Sr, and Ba by calixarenes with oxygen donor atoms improves, allowing the separation from alkali ions.131 The competition by alkali ions is lower than in crown ether extraction systems. Separation factors S with CA2 in nitrobenzene are log S = 7 (Ca), 5.5 (Sr), and 5.4 (Ba). 

To increase the distribution ratios, a solution of lithium nitrate 1M was used. This salt, which has a common anion with europium and americium to be extracted but a cation which is usually negligibly extracted by other calixarenes, should increase the distribution ratios according to the relation Du = A (JU "[N03- ". It seems that these calixarenes, as several nitrogen ligands do, present a certain affinity for this lithium cation. The lipophilic dicarbollide anion (BrCosan), which is known to facilitate cation extraction, was implemented and led to a strong increase of the extraction of cations from 10 3 M HN03 solutions. Under these conditions, only thiopicolinamide was not able to significantly extract trivalent actinides.187... 

Kyrs, M., Svoboda, K., Lhotak, P., Alexova, J. Synergistic solvent extraction of Eu, Sr and Cs into chlorobenzene solutions of the three conformers of tetrathiocalixarene and dicarbollide. J. Radioanal. Nucl. Chem. (2003), 258 (3), 497-509. 

Reinoso-Garcra, M.M., Verboom, W., Reinhoudt, D.N., Brisach, R, Arnaud-Neu, R, Liger, K. Solvent extraction of actinides and lanthanides by CMP(O)- and N-acyl(thio) urea-tetrafunctionalized cavitands Strong synergistic effect of cobalt bis(dicarbollide) ions. Solvent Extr. Ion Exch. (2005), 23 (3), 425-437. 

Coupez, B., Wipff, G. The synergistic effect of cobalt-dicarbollide anions on the extraction of M3+ lanthanide cations by calix[4]arenes A molecular dynamics study at the water- oil interface. C.R. Chimie (2004) 7(12), 1153-1164. 

Krejzler, J., Narbutt, J., Foreman, M.R.St.J., Hudson, M.J., Casensky, B., Madic, C. Solvent extraction of Am(III) and Eu(III) from nitrate solution using synergistic mixtures of N-tridentate heterocycles and chlorinated cobalt dicarbollide. Czech. J. Phys. (2006), 56 (Suppl. D), D459-D467. 

Shishkin, D.N., Galkin, B.Ya.,Fedorov,Yu.S.,Zilberman, B.Ya.,Shmidt,O.V.Partitioning of high-level waste with an extractant based on chlorinated cobalt dicarbollide and dibu-tylphosphoric acid zirconium salt. Radiochemistry (2003), 45 (6), 577-580. 

This review groups the information published on degradation of the main families of extractants studied in the frame of long-lived minor-actinide and fission-product recovery (1-4) (see Chapter 1) alkyl-phosphorus compounds (phosphates, phosphonic acids, bifunctional compounds like CMPO), amide compounds (dialkyl-amides, malonamides, and diglycolamides), N-donor compounds, and macrocycles like crown ethers and calixarenes (Table 8.1). The multicomponent systems based on the chlorinated cobalt dicarbollide process have not been considered. 

The 3.3-cm Russian contactors were used to test a cobalt-dicarbollide-based solvent-extraction process for separating Cs, Sr, and the actinides from dissolved HLW (Law et al., 2001, Herbst et al., 2002). These contactors were designed and fabricated in Moscow, Russia, by the Research and Development Institute of Construction Technology (NIKIMT). They are operated at 2700 rpm and have a nominal throughput of 417 mL/min (25 L/h). Figure 10.25 shows the 26-stage 3.3-cm contactor bank used in these tests. A recent summary of this work is given by Romanovskiy et al. (2005). 

Herbst, R. S., J. D. Law, T. A. Todd, et al. 2002. Development and Testing of a Cobalt Dicarbollide Based Solvent Extraction Process for the Separation of Cesium and Strontium from Acidic Tank Waste. Sep. Sci. Technol., 37(8), 1807-1831. 

Coupez, B., Wipff, G. (2004), The Synergistic Effect of Cobalt-dicarbollide Anions on the Extraction of M Lanthanide Cations by Calix[4]arene-CMPO ligands a Molecular Dynamics Study at the Water-"oil" Interface, C. R. Chimie Acad. Sc. Paris, in press. 

---