On the use of pseudo-protic ionic liquids to extract gold(III) from HCl solutions
Solvent extraction of gold(III) from HCl media using pseudo-protic ionic liquids (PPILs) dissolved in toluene as the extractant phase is investigated. Three PPILs are generated from the reaction of commercially available amines and 1 M HCl solution and named as pri-NH<sub>2</sub>H<sup...
| Autores: | , |
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| Formato: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2023 |
| País: | España |
| Recursos: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repositorio: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:digital.csic.es:10261/308039 |
| Acesso em linha: | http://hdl.handle.net/10261/308039 |
| Access Level: | acceso abierto |
| Palavra-chave: | Gold(III) Hydrochloric acid Pseudo-protic ionic liquids Extraction Stripping Zero gold valent Nanoparticles |
| Resumo: | Solvent extraction of gold(III) from HCl media using pseudo-protic ionic liquids (PPILs) dissolved in toluene as the extractant phase is investigated. Three PPILs are generated from the reaction of commercially available amines and 1 M HCl solution and named as pri-NH<sub>2</sub>H<sup>+</sup>Cl<sup>−</sup> (derived from the primary amine Primene 81R), sec-NHH<sup>+</sup>Cl<sup>−</sup> (derived from the secondary amine Amberlite LA2) and ter-NH<sup>+</sup>Cl<sup>−</sup> (derived from the tertiary amine Hostarex A327). In the above structures, -NH<sub>2</sub>H<sup>+</sup>Cl<sup>−</sup>, -NHH<sup>+</sup>Cl<sup>−</sup> and -NH<sup>+</sup>Cl<sup>−</sup> represented the active groups (anion exchangers) of the respective PPIL. In the case of gold(III) extraction, the experimental variables investigated included the equilibration time (2.5–30 min), temperature (20–60 °C), HCl concentrations (1–10 M) in the aqueous phase, gold(III) concentration (0.005–0.05 g/L) in this same phase, and PPILs concentrations in the organic phase. From the experimental data, and using the Specific Interaction Theory, the interaction coefficients (ε) for the pair AuCl<sub>4</sub><sup>−</sup>, H<sup>+</sup> are estimated for the systems involving the three PPILs. Gold(III) is recovered from the metal-loaded organic phases using sodium thiocyanate solutions, and from these, gold is finally recovered by the precipitation of zero-valent gold (ZVG) nanoparticles. |
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