The correlactionship of bacterial population and oxidation-reduction potential in the bioleaching of sulfuric minerals by bacterial strain of Aciditiobacilus Ferrooxidans isolated from acid mine effluent was studied. The solubilization of copper and gold release from a mineral with sulphides exceeding 80% was evaluated. The experimental variables were: Pulp density at 1, 2 and 6% (W/V), concentration of ferrous sulfate as part of the 9k medium of 0, 3, 6, 9 and 15 gr/L.; maintaining constant temperature and pH. The tests were carried out in three consecutive stages, starting with inoculum containing 7.05x107 Cell/mL and then the one obtained in each previous stage, observing the variation in the periods of adaptation and growth. In the first stage the maximum bacterial density reached in 24 days was 4.75x107 Cell/mL with 6 g/L of ferrous sulfate. In the second stage a maximum density of ...

The worldwide demand for silver is increasing due to the technological development in different areas, especially for the requirements in the production of renewable energies; therefore, for the treatment of refractory minerals by conventional processes, it is necessary to study mechanisms to identify the viability of their processing and the feasibility of their recovery, ensuring profitability. Gold and silver present in the matrix of sulfide-based ores are not affordably recovered by the conventional method involving leaching in sodium cyanide solution. Therefore, it must be subjected to oxidation pretreatment or conversion of the sulfides to simple compounds that allow recovery of the precious metals. The methods of oxidation of minerals considered refractory are carried out by hydro and pyrometallurgical methods, seeking the dissolution of sulfur, iron, arsenic and other elements pr...

This work describes the isolation and selection of bacterial strains of the genus Pseudomonas in Cetrimide, Acetamide and King B Agar media, from effluents of the leaching process and from the tailings deposit of the gold ore processing plant, Caraveli - Arequipa. Subsequently, the adaptation was made in Modified Mineral Medium (M9M), to different concentrations of sodium cyanide, to evaluate the tolerance and degradation of the CN- radical. The results of sowing in different nutrient media allowed us to observe changes in coloration with a change from clear to intense red in Acetamide Medium and from clear to fluorescent green in King B Agar Medium, revealing the presence of P. pseudoalcaligenes bacteria. Similarly, during the adaptation process of a strain whose initial cell population was 2.0E+06 CFU/mL, in media supplemented with 50, 100, 150, 200 and 250 ppm of Free Cyanide, at the ...

Although it is true that the higher education institutions in engineering since their creation, formulate as a scientific and technological statement as the sole purpose of justifying their existence and validity.

Although it is true that the higher education institutions in engineering since their creation, formulate as a scientific and technological statement as the sole purpose of justifying their existence and validity.

Lleva a cabo la biolixiviación de minerales sulfurados con alto contenido metálico, mediante cepas nativas de Acidithiobacillus ferrooxidans aisladas de efluentes ácido de mina de la región de Huancavelica. Las pruebas se llevaron a cabo en tres etapas de 24 días cada una, primero inoculando la bacteria adaptada en pulpa de mineral y en la segunda y tercera etapa inoculando las usadas en las etapas anteriores, respectivamente. Las principales condiciones fueron: temperatura ambiente (20°C), agitación 150 rpm, pH 2.0 y medio líquido con diversas concentraciones de sulfato ferroso y mineral sulfurado; teniendo como objetivo extraer el cobre y monitorear la dinámica del crecimiento poblacional bacteriano. Mediante el uso de los modelos sigmoideos de Benjamín Gompertz y Pierre François Verhulst, se ha representado paramétrica y gráficamente el crecimiento poblacional de las bact...