Extractions with metal-dithiocarbamates as reagents

Abstract

The metal-dlthlocarbamates Hg(DDC)₂, Ag(DDC), Ni(DDC)₂, Cu(DDC)₂, Sb(DDC)₃, Te(DDC)₄, Se(DDC)₃, ln(DDC)₃, As(DDC)₃, Cd(DDC)₂, Zn(DDC)₂, Co(DDC)₃, Fe(DDC)₃, and TI(DDC) have been tested as reagents for the extraction of 12 different metals from 0.1 N 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.