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Cobalt recovery from mixed Co–Mn hydroxide precipitates by ammonia–ammonium carbonate leaching / A. Katsiapi in Minerals engineering, Vol. 23 N° 8 (Juillet 2010) 

Public ISBD [article]  in Minerals engineering > Vol. 23 N° 8 (Juillet 2010) . - pp. 643–651 Titre : Cobalt recovery from mixed Co–Mn hydroxide precipitates by ammonia–ammonium carbonate leaching Type de document : texte imprimé Auteurs : A. Katsiapi, Auteur ; P.E. Tsakiridis, Auteur ; P. Oustadakis, Auteur Année de publication : 2011 Article en page(s) : pp. 643–651 Note générale : Génie Minier Langues : Anglais (eng) Mots-clés : Cobalt  Manganese  Precipitation  Ammoniacal  leaching Résumé : The research work presented in this paper focused on the recovery of cobalt from mixed Co–Mn hydroxide precipitates (obtained from sulphate leach liquors of nickel oxide ore), using ammonia–ammonium carbonate leaching. The characterization of the initial mixed hydroxide precipitates, as well as the corresponding leached residue was carried out by X-ray Diffraction, TG–DTA and Scanning Electron Microscopy. Cobalt and manganese precipitation was based on the statistical design and analysis of experiments, in order to determine the main effects and interactions of the precipitation factors, which were the equilibrium pH and the temperature. Co and Mn were precipitated as hydroxides at pH = 10.5 and T = 25 °C, using 5 M NaOH as a neutralizing agent, by 99.9% and 99.5%, respectively. The main mineralogical phases were, Mn3O4 (Hausmannite), γ-Mn3O4 and CoMn2O4, while Co(OH)2 and Mn(OH)2 (Pyrochroite) were also present as minor constituents. Cobalt and manganese separation was based on selective cobalt recovery by ammonia–ammonium carbonate leaching of the produced mixed hydroxide precipitate. The factors studied were the ammonia–ammonium carbonate concentration and the solid to liquid ratio. The cobalt recovery efficiency reached 93%. Mn3O4 (Hausmannite) was the main mineralogical phase of the leached residue, while MnCO3 (Rhodochrosite) and Mn2O3 were also present. Small quantities of cobalt were also observed in the residue as CoMn2O4. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687510000622 [article] Cobalt recovery from mixed Co–Mn hydroxide precipitates by ammonia–ammonium carbonate leaching [texte imprimé] / A. Katsiapi, Auteur ; P.E. Tsakiridis, Auteur ; P. Oustadakis, Auteur . - 2011 . - pp. 643–651. Génie Minier Langues : Anglais (eng) in Minerals engineering > Vol. 23 N° 8 (Juillet 2010) . - pp. 643–651 Mots-clés : Cobalt  Manganese  Precipitation  Ammoniacal  leaching Résumé : The research work presented in this paper focused on the recovery of cobalt from mixed Co–Mn hydroxide precipitates (obtained from sulphate leach liquors of nickel oxide ore), using ammonia–ammonium carbonate leaching. The characterization of the initial mixed hydroxide precipitates, as well as the corresponding leached residue was carried out by X-ray Diffraction, TG–DTA and Scanning Electron Microscopy. Cobalt and manganese precipitation was based on the statistical design and analysis of experiments, in order to determine the main effects and interactions of the precipitation factors, which were the equilibrium pH and the temperature. Co and Mn were precipitated as hydroxides at pH = 10.5 and T = 25 °C, using 5 M NaOH as a neutralizing agent, by 99.9% and 99.5%, respectively. The main mineralogical phases were, Mn3O4 (Hausmannite), γ-Mn3O4 and CoMn2O4, while Co(OH)2 and Mn(OH)2 (Pyrochroite) were also present as minor constituents. Cobalt and manganese separation was based on selective cobalt recovery by ammonia–ammonium carbonate leaching of the produced mixed hydroxide precipitate. The factors studied were the ammonia–ammonium carbonate concentration and the solid to liquid ratio. The cobalt recovery efficiency reached 93%. Mn3O4 (Hausmannite) was the main mineralogical phase of the leached residue, while MnCO3 (Rhodochrosite) and Mn2O3 were also present. Small quantities of cobalt were also observed in the residue as CoMn2O4. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687510000622