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Mössbauer quantification of pyrrhotite in relation to self-heating / A. Navarra in Minerals engineering, Vol. 23 N° 8 (Juillet 2010) 

Public ISBD [article]  in Minerals engineering > Vol. 23 N° 8 (Juillet 2010) . - pp. 652–658 Titre : Mössbauer quantification of pyrrhotite in relation to self-heating Type de document : texte imprimé Auteurs : A. Navarra, Auteur ; J.T. Graham, Auteur ; S. Somot, Auteur Année de publication : 2011 Article en page(s) : pp. 652–658 Note générale : Génie Minier Langues : Anglais (eng) Mots-clés : Analytical  methods  Mass  balancing  Sulphide  ores  Ore  handling  Ore  mineralogy Résumé : Pyrrhotite (Po) is widely considered the most significant mineral in the self-heating of sulphide ores and concentrates. It is therefore desirable to determine the amount of Po in a sample. This is commonly accomplished through X-ray diffraction (XRD) or quantitative evaluation of materials by scanning electron microscopy (QEM–SEM), neither of which are suited to oxidizing samples such as Po. The sample preparation for these methods often requires heating and drying, which may alter the composition. This paper introduces another quantitative method based on Mössbauer analysis, whose sample preparation is limited, and not as likely to alter the sample. The technique is tested using binary and ternary mixtures containing pyrrhotite with pentlandite (Pn), pyrite (Py) and sphalerite (Sp). A detection limit of 2 wt.% Po is easily obtained in the Po–Pn binary mixtures. The Po is also successfully measured in Pn–Po–Py and Sp–Po–Py mixtures; however, the presence of sphalerite increases the time required for an accurate measurement. The time required to measure Po in complex samples may be optimized through future work. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687510000932 [article] Mössbauer quantification of pyrrhotite in relation to self-heating [texte imprimé] / A. Navarra, Auteur ; J.T. Graham, Auteur ; S. Somot, Auteur . - 2011 . - pp. 652–658. Génie Minier Langues : Anglais (eng) in Minerals engineering > Vol. 23 N° 8 (Juillet 2010) . - pp. 652–658 Mots-clés : Analytical  methods  Mass  balancing  Sulphide  ores  Ore  handling  Ore  mineralogy Résumé : Pyrrhotite (Po) is widely considered the most significant mineral in the self-heating of sulphide ores and concentrates. It is therefore desirable to determine the amount of Po in a sample. This is commonly accomplished through X-ray diffraction (XRD) or quantitative evaluation of materials by scanning electron microscopy (QEM–SEM), neither of which are suited to oxidizing samples such as Po. The sample preparation for these methods often requires heating and drying, which may alter the composition. This paper introduces another quantitative method based on Mössbauer analysis, whose sample preparation is limited, and not as likely to alter the sample. The technique is tested using binary and ternary mixtures containing pyrrhotite with pentlandite (Pn), pyrite (Py) and sphalerite (Sp). A detection limit of 2 wt.% Po is easily obtained in the Po–Pn binary mixtures. The Po is also successfully measured in Pn–Po–Py and Sp–Po–Py mixtures; however, the presence of sphalerite increases the time required for an accurate measurement. The time required to measure Po in complex samples may be optimized through future work. DEWEY : 622 ISSN : 0892-6875 En ligne : http://www.sciencedirect.com/science/article/pii/S0892687510000932