M actinides

J. M. Haschke, ia G. Meyer and L. R. Morss, eds.. Synthesis ofEanthanide and Actinide Compounds, Kluwer Academic PubUshers, Dordrecht, the 

Actinide complexes with carboxylic acids. U. Casellato, P. A. Vigato and M. Vidali, Coord. Chem. Rev., 1978, 26, 85-159 (276). 

F. L. Getting, M. H. Rand, and R. J. Ackermaim, ia F. L. Oettiag, ed.. The Chemical Thermodynamics of Actinide Elements and Compounds, Part 1, The Actinide Elements, SHlPDBj424j 1, IAEA, Vienna, Austria, 1976. 

M. S. S. Brooks, Actinides—Chemistry and Py.sica Properties L. Manes, Ed., 261, Springer-Verlag, Berlin (1985). 

Year Nuclear power capacity, GWe Volume, 10 m Actinide mass, MT Radioactivity, MCi Thermal power, MW 

Hydroxides. Thorium (TV) is generally less resistant to hydrolysis than similarly sized lanthanides, and more resistant to hydrolysis than tetravalent ions of other early actinides, eg, U, Np, and Pu. Many of the thorium(IV) hydrolysis studies indicate stepwise hydrolysis to yield monomeric products of formula Th(OH) , where n is integral between 1 and 4, in addition to a number of polymeric species (40—43). More recent potentiometric titration studies indicate that only two of the monomeric species, Th(OH) " and thorium hydroxide [13825-36-0], Th(OH)4, are important in dilute (<10 M Th) solutions (43). However, in a Th02 [1314-20-1] solubiUty study, the best fit to the experimental data required inclusion of the species. Th(OH) 2 (44). In more concentrated (>10 Af) solutions, polynuclear species have been shown to exist. Eor example, a more recent model includes the dimers Th2(OH) " 2 the tetramers Th4(OH) " g and Th4(OH) 2 two hexamers, Th2(OH) " 4 and Th2(OH) " 2 (43). 

The abbreviations for the investigation methods are also taken from the nomenclature of Sillen and Martel 1 (76) aiex = anion exchange cal = calorimetry ciex = cation exchange dis = distribution between two phases est = estimate red = e.m.f. with redox electrode sp = spectrophotometry. Our selected data, rather limited in number, arise from the present status of the IAEA assessment of inorganic complexes of the actinides (12). 

Thenoyltrifluoroacetone(TTA), C4H3S,CO,CH2,COCF3. This is a crystalline solid, m.p. 43 °C it is, of course, a /1-diketone, and the trifluoromethyl group increases the acidity of the enol form so that extractions at low pH values are feasible. The reactivity of TTA is similar to that of acetylacetone it is generally used as a 0.1-0.5 M solution in benzene or toluene. The difference in extraction behaviour of hafnium and zirconium, and also among lanthanides and actinides, is especially noteworthy. 

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