A classical modelling of abandoned mine tailings' bioleaching by an autochthonous microbial culture

The aim of this study was to study and model the bioleaching of abandoned mine tailings at different pulp densities 1–20% w/v by using an autochthonous mesophilic microbial culture. Because of the importance of the ferrous-iron oxidation as sub-process on the bioleaching of sulphide mineral ores, th...

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Detalles Bibliográficos
Autores: Medina Díaz, Hassay Lizeth, Acosta Hernández, Irene, Muñoz, Martín, López-Bellido Garrido, Francisco Javier, Villaseñor Camacho, José, Llanos López, Javier, Rodríguez, Luis, Fernández Morales, Francisco Jesús
Tipo de recurso: artículo
Fecha de publicación:2022
País:España
Institución:Universidad de Castilla-La Mancha
Repositorio:RUIdeRA. Repositorio Institucional de la UCLM
OAI Identifier:oai:ruidera.uclm.es:10578/30537
Acceso en línea:http://hdl.handle.net/10578/30537
Access Level:acceso abierto
Palabra clave:Modelling
Bioleaching
Mine tailings
Rate kinetics
Iron-oxidizing microorganisms
Modelización
Biolixiviación
Microorganismos oxidantes del hierro
Tasa de cinética
Desechos de la minería
Descripción
Sumario:The aim of this study was to study and model the bioleaching of abandoned mine tailings at different pulp densities 1–20% w/v by using an autochthonous mesophilic microbial culture. Because of the importance of the ferrous-iron oxidation as sub-process on the bioleaching of sulphide mineral ores, the ferrous-iron oxidation process by the autochthonous microbial culture was studied at different ferrous-iron concentrations. A mathematical model fitted to the experimental results and the main kinetic and stoichiometric parameters were determined, being the most relevant the maximum ferrous-iron oxidation rate 5.1 (mmol Fe2+/mmol C·h) and the biomass yield, 0.01 mmol C/mmol Fe2+, values very similar to that of mixed cultured dominated by Leptospirillum strains. This autochthonous culture was used in the bioleaching experiment carried out at different pulp densities, obtaining a maximum metal recovery in the tests carried out at 1% w/v, recovering a 90% of Cd, 60% of Zn, 30% of Cu, 25% Fe and 6% of Pb. Finally, the different leaching mechanisms were modelled by using the pyrite as ore model obtaining a bioleaching rate of 0.316 mmol Fe2+/(L·h) for the direct mechanisms and a bioleaching rate for the indirect and cooperative leaching mechanisms of 0.055 Fe2+/(L·h).