Extractions with metal-dithiocarbamates as reagents (including Hg, Ag, Bi, Cu, Cd, In, Sb, Zn, Te Co, As, and Fe)

The metal--dithiocarbamates Hd(DDC)2, Ag(DDC), Ni(DDC)2, Cu(DDC)2, Sb(DDC)3, Te(DDC)4, Se(DDC)3, In(DDC)3, As(DDC)3, Cd(DDC)2, Zn(DDC)2, Co(DDC)3, Fe(DDC)3, and Tl(DDC) were tested as reagents for the extraction of 12 different metals (including Hg, Ag, Bi, Cu, Cd, In, Sb, Zn, Te, Co, CAs, and Fe) from 0.1N H2SO4 and from solutions of pH 5 into CHCl3. These reagents show excellent selectivity for the extraction of metals with higher conditional extraction constants. In the majority of all cases, extraction is complete within 2 minutes; Se(DDC)4, Co(DDC)3, and Fe(DDC)3, however, react only slowly and in some cases incompletely or not at all. The successive extraction of a sample with several different reagents yields a series of organic fractions that contain different metals. As an example, the application of these reagents to a neutron activated biological sample is given, where the resulting organic fractions can be directly submitted to γ-spectrometry without any further chemical treatment. (U.S.)