Thiourea-based coordinating polymers: synthesis and binding to noble metals

The synthesis of several coordinating polymers by grafting thiourea functional groups onto commercial macroporous polystyrene polymer matrices are described. In this paper, we also report the study on the absorption and elution of precious metal ions (or together with base metal ions, Cu²⁺ and Fe³⁺) from acidic chloride solutions. The results showed that these resins have appreciable capacity and good selectivity for the absorption of gold from acidic solutions. The extraction kinetics of the resins is slower than the corresponding monomolecular ‘free’ extractant analogues. However, some of the resins show acceptable extraction rates.