Curium hydroxide

A number of compounds of curium have been produced, including two forms of curium oxide (Cm203 and Cm02), two forms of curium fluoride (CmF3 and CmF4), curium chloride (CmCl3), curium bromide (CmBr3), and curium hydroxide (Cm(OH)3). 

In comparison to plutonium both americium and curium are taken up by plants quite readily. The concentration factors for both americium and curium are 10-4 to 10-2 (127). While plutonium has been the subject of considerable research into its environmental impact there have been few investigations into americium and curium. Bondi-etti et al (94) have concluded that plutonium hydroxide polymers would be resistant... 

Many compounds of curium are known. They include the oxides, Cm02 and Cm203, fluorides CmF4 and CmFs, other halides, CmXa hydroxide, Cm(OH)3, and oxalate Cm2(C204)3. The oxide, hydroxide, fluoride, and oxalate salts are insoluble in water and may be obtained by precipitation reactions. 

Curium was first isolated in Ihe form of a pure compound, the hydroxide, of curium—242 (produced by the neutron irradiation ol aincncium-241) hy Werner and Perlmun at the University of California in the autumn of 1947. Much of the earlier work wiili curium used the isotopes J Cm and wCm, but the heavier isotopes oiler greater advantages mainly because of llicir longer half-lives. The isotope obtainable in relatively high... 

Curium — (Pierre and Marie Curie), Cm at. wt. (247) at. no. 96 m.p. 1345°C sp. gr. 13.51 (calc.) valence 3 and 4. Although curium follows americium in the periodic system, it was actually known before americium and was the third transuranium element to be discovered. It was identified by Seaborg, James, and Ghiorso in 1944 at the wartime Metallurgical Laboratory in Chicago as a result of heUum-ion bombardment of Pu in the Berkeley, California, 60-inch cyclotron. Visible amounts (30 pg) of in the form of the hydroxide, were first isolated by Werner and Perlman... 

Curium oxalate, Cm2(C204)3, is routinely used for calcination to Cm02. Oxalate precipitation has also been used to process kilograms of Cm, with subsequent metathesis with 0.5 m hydroxide to Cm(OH)3 [90,91]. 

Desire, Hussonnois and GuUlaumont (1969) determined stability constants for the species AnOH + for the actinides, plutonium(III), americium(III), curium (III), berkelium(III) and californium (III) using a solvent extraction technique. The stability constants obtained for americium(III) and curium(III) are two orders of magnitude larger than other similar data available in the literature. The stability constants of the lanthanide(III) and actinide(III) ions are very difficult to obtain using solvent extraction due to problems associated with attainment of maximum extraction into the solvent phase before the narrow band of pH between the onset of hydrolysis reactions and the precipitation of solid hydroxide phases. Consequently, the data of Desire, Hussonnois and GuUlaumont (1969) are not retained in this review. 

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