Bioleaching of a complex nickel–iron concentrate by mesophile bacteria.

This work investigates the bioleaching of a complex nickel–iron concentrate (pentlandite, pyrrhotite, and minor amounts of chalcopyrite) using acidophile iron-oxidizing bacteria. It aims to improve the understanding of the mechanism of bacterial action on nickel sulphide bioleaching. The effects of...

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Bibliographic Details
Authors: Santos, Luciano Rodrigo Gomes, Barbosa, Alexandre Ferraz, Souza, Adelson Dias de, Leão, Versiane Albis
Format: article
Status:Published version
Publication Date:2006
Country:Brasil
Institution:Universidade Federal de Ouro Preto (UFOP)
Repository:Repositório Institucional da UFOP
Language:English
OAI Identifier:oai:repositorio.ufop.br:123456789/5532
Online Access:http://www.repositorio.ufop.br/handle/123456789/5532
https://doi.org/10.1016/j.mineng.2006.03.001
Access Level:Open access
Keyword:Particle morphology
Bioleaching
Sulphide ore
Description
Summary:This work investigates the bioleaching of a complex nickel–iron concentrate (pentlandite, pyrrhotite, and minor amounts of chalcopyrite) using acidophile iron-oxidizing bacteria. It aims to improve the understanding of the mechanism of bacterial action on nickel sulphide bioleaching. The effects of the external addition of Fe(II) and the mineralogical assembly on the extraction of nickel are evaluated. A high nickel extraction (around 70%) can be achieved in batch experiments. Moreover, the external addition of iron has not shown any effect on the extraction of the metal, emphasizing the importance of pyrrhotite dissolution in the first step of bioleaching. It was also examined the morphological features of the sulphides as well as the leach residues and reactions products formed during bioleaching. It was noticed that elemental sulphur was produced on pyrrhotite surfaces, which dissolves ahead of pentlandite. A discussion on how galvanic interactions affect the reactivity of sulphide mineral and the formation of bioleaching products is also presented.