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Kinetics of saprolitic laterite leaching by sulphuric acid at atmospheric pressure / Wei Luo in Minerals engineering, Vol. 23 N° 6 (Mai 2010) 

Public ISBD [article]  in Minerals engineering > Vol. 23 N° 6 (Mai 2010) . - pp. 458–462 Titre : Kinetics of saprolitic laterite leaching by sulphuric acid at atmospheric pressure Type de document : texte imprimé Auteurs : Wei Luo, Auteur ; Qiming Feng, Auteur ; Leming Ou, Auteur Année de publication : 2011 Article en page(s) : pp. 458–462 Note générale : Génie Minier Langues : Anglais (eng) Mots-clés : Oxide  ores  Ore  mineralogy  Leaching  Reaction  kinetics Résumé : Mineralogical analyses of the saprolitic laterite material have been characterized by X-ray fluorescence (XRF), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, thermal analysis, scanning electron microscope (SEM) and energy dispersive X-ray analysis (EDAX). Results showed that the saprolitic laterite material consists mainly of nickel-substituted lizardite showing the pebble-like morphology and traces of magnetite and phlogopite. Leaching results showed that as much as 84.8% nickel could be leached under the experimental conditions of 10% (v/v) H2SO4, 90 °C reaction temperature, leached within 5 min, particle size d50 = 25 μm, stirring at 500 rpm and liquid to solid ratio 3:1. The kinetics of nickel and magnesium leaching from the saprolitic laterite material have been investigated in a mechanically stirred reactor and the activation energies were determined to be 53.9 kJ mol−1 for nickel and 59.4 kJ mol−1 for magnesium respectively, which are characteristic for a chemical reaction controlled process. The similarity of the activation energies of nickel and magnesium leaching from the saprolitic laterite material by sulphuric acid means that nickel in lizardite is loosely bound within the octahedral layer and almost all of the nickel could be leached simultaneously with magnesium but without complete decomposition of the silicate structure. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S089268750900260X [article] Kinetics of saprolitic laterite leaching by sulphuric acid at atmospheric pressure [texte imprimé] / Wei Luo, Auteur ; Qiming Feng, Auteur ; Leming Ou, Auteur . - 2011 . - pp. 458–462. Génie Minier Langues : Anglais (eng) in Minerals engineering > Vol. 23 N° 6 (Mai 2010) . - pp. 458–462 Mots-clés : Oxide  ores  Ore  mineralogy  Leaching  Reaction  kinetics Résumé : Mineralogical analyses of the saprolitic laterite material have been characterized by X-ray fluorescence (XRF), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, thermal analysis, scanning electron microscope (SEM) and energy dispersive X-ray analysis (EDAX). Results showed that the saprolitic laterite material consists mainly of nickel-substituted lizardite showing the pebble-like morphology and traces of magnetite and phlogopite. Leaching results showed that as much as 84.8% nickel could be leached under the experimental conditions of 10% (v/v) H2SO4, 90 °C reaction temperature, leached within 5 min, particle size d50 = 25 μm, stirring at 500 rpm and liquid to solid ratio 3:1. The kinetics of nickel and magnesium leaching from the saprolitic laterite material have been investigated in a mechanically stirred reactor and the activation energies were determined to be 53.9 kJ mol−1 for nickel and 59.4 kJ mol−1 for magnesium respectively, which are characteristic for a chemical reaction controlled process. The similarity of the activation energies of nickel and magnesium leaching from the saprolitic laterite material by sulphuric acid means that nickel in lizardite is loosely bound within the octahedral layer and almost all of the nickel could be leached simultaneously with magnesium but without complete decomposition of the silicate structure. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S089268750900260X