Gold, platinum and palladium extractants and recovery methods

摘要

To provide an extraction agent of a gold compound, a platinum compound and a palladium compound which has low viscosity, facilitates handling, has no concern of generation of a peroxide in long-term use, has large extraction efficiency, and is water-soluble.SOLUTION: An extraction agent is aliphatic amide which absorbs moisture and has a lower limit critical solution temperature in a state of diluted solution, and its representative compound includes N,N-diisopropyl acetamide, N-propyl propanamide, N-diethyl butanamide, N, N, N', N'-tetrapropyl malonamide, N-(2-(diethylamino)ethyl)butanamide, and N, N', N"-triethylbenzene-1,3,5-tricarboxamide. A recovery method includes uniformly mixing an aqueous solution containing gold, platinum and palladium with the extraction agent, heating the mixture to a lower limit critical solution temperature or higher to phase-separate the mixture into an extraction agent phase containing gold, platinum and palladium and a water phase, and separating and reducing the extraction agent phase by liquid-liquid separation to precipitate and recover metal.SELECTED DRAWING: None