CP/MAS NMR (13C, 15N, and 113Cd), thermal behavior, and sorption properties of cadmium Di-iso-butyldithiocarbamate. The gold(III)-binding species sorbed from solutions

The structure and thermal behavior of cadmium di-iso-butyldithiocarbamate (I) have been studied by solid-state 13C and 15N CP/MAS NMR and simultaneous thermal analysis (STA). The cadmium complex forms two crystalline polymorphs, α and β. The structure of each of the polymorphs contains two structurally nonequivalent binuclear [Cd2{S2CN(iso-C4H9)2}4] molecules. The STA data have shown the possibility of the α-I → β-I phase transition. Studying the thermal behavior of the complex has demonstrated that the end product of thermodestruction is a fine yellow-orange powder of CdS. The sorption properties of I have been studied with respect to gold(III) chloride solutions in 2 M HCl. It has been found that gold(III) is efficiently sorbed from strong acid solutions in the Au3+ concentration range 0.032–3.220 mg/mL. On the basis of multinuclear (13C, 15N, and 113Cd) MAS NMR data, it has been demonstrated that the individual gold(III)-binding species in the sorption system is the ionic gold(III) cadmium-complex of composition [Au{S2CN(iso-C4H9)2}2]2[CdCl4].