The leaching of copper ores produces a rich solution with metal interferences. In this context, Fe(III), Zn(II), and Mn(II) are three metals contained in industrial copper-rich solutions in high quantities and eventually can be co-extracted with the copper. The purpose of the current study was to determine the feasibly of solvent extraction with the use of ionic liquid methyltrioctyl/decylammonium bis (2,4,4-trimethylpentyl)phosphinate (R₄NCy) as an extractant of Cu(II) in the presence of Fe(III), Zn(II), and Mn(II). In general terms, the results showed a high single extraction efficiency of all the metals under study. In the case of Fe(III) and Zn(II), the extraction was close to 100%. On the contrary, the stripping efficiency was poor to Fe(III) and discrete to Zn(II), but very high to Cu(II) and Mn(II). Finally, the findings of this study suggest that the ionic liquid R₄NCy is feasible for the pre-treatment of the copper solvent extraction process to remove metal impurities such as Fe(III) and Zn(II).

Recent works suggest that the use of ionic liquids in the copper solvent extraction industry is feasible. However, the reports did not use real solutions (or synthetic solutions with various elements). This fact remains poorly established, and the interaction efficiencies are still under study. The objective of this research is to explore the extraction and stripping of the four major elements present in a copper industrial pregnant leach solution (Cu(II), Fe(III), Mn(II), and Zn(II)) using the methyltrioctyl/decylammonium bis(2,4,4-trimethylpentyl)phosphinate (R₄NCy) ionic liquid as an extractant. The work conditions studied in extraction were ionic liquid concentration, initial pH, and O/A ratio, and in stripping were H₂SO₄ concentration and O/A ratio. The test was carried out at room temperature and ambient pressure. High efficiency and selectivity (99.82% and 113,755 over Cu(II), respectively) were observed for Fe(III) extraction over the other elements. Moreover, after the extraction test, significant difficulty in stripping Fe(III) loaded in the ionic liquid was observed (28.7% at 0.5 M of H₂SO₄). Finally, the present study demonstrates that the R₄NCy ionic liquid is not suitable for copper extraction because it has a higher selectivity for Fe(III) and Zn(II).

Los ácidos orgánicos y principalmente el ácido cítrico generan daños en estructuras de concreto, comprometiendo su correcto desempeño. Por otra parte, el concreto residual (CR) es un problema ambiental debido a los grandes volúmenes generados requiriendo para su correcta disposición amplias extensiones de terrenos. El objetivo de este estudio fue caracterizar química y mineralógicamente el CR y evaluar la disolución de calcio y silicio con ácido cítrico, con el fin de determinar su uso potencial como fuente de estos elementos para suelos degradados. La caracterización permitió identificar como elementos mayoritarios el calcio y el silicio asociados a las fases del concreto como la calcita, portlandita y alumino-silicatos de calcio hidratados. La extracción de calcio y silicio fue investigada mediante análisis químico y mineralógico sobre concreto residual sumergido en solución de ácido cítrico por dos días a 28 °C y 110 rpm controlando y no controlando el pH. Debido a la concentración de calcio y silicio en solución se pudo verificar que estos residuos luego de la acidulación podrían ser empleados como fuente de nutrientes para suelos degradados antrópicamente.

The entrainment of the organic phase in the aqueous applied to typical solutions in a solvent extraction of copper process was studied. The organic phase used is composed of the commercial extractant LIX 984-N diluted in Shellsol 2046 AR. The aqueous phase contains 6 g/L of Cu2+, at pH 2 and 20 ºC. The variables studied were: mixing speed of 400 to 1000 rpm; mixing time of 3 to 30 minutes; initial pH of the electrolyte 2, 3, and 4; percentage of extractant in the organic phase 10 to 30% v/v; and copper concentration in the aqueous phase 1 to 6 g/L. It was determined that the entrainment of the organic phase in the aqueous is determined by the physical properties of the phases in equilibrium and by the system’s hydrodynamics, and it is a phenomenon that involves the advancing speed of the interphase (or dispersion band) and the displacement speed of the organic drops.

In this work, the effect of the pre-treatment of bornite concentrate with a sodium chloride–sulfuric acid mixture prior to leaching with chloride solutions was evaluated. The influence of the dosage of NaCl and the resting time in the copper solution was evaluated. The solid residues of the pre-treatment were characterized by XRD to evaluate the changes that took place in the bornite. The experimental results show that as the sitting time and the amount of sodium chloride added are increased, the dissolution of the sulfide species also increased. The pre-treatment affects Cu preferentially because it has greater mobility than iron in the bornite crystal lattice. The pre-treatment promotes the formation of soluble Cu and Fe species. The efficiency of the pre-treatment depends largely on the formation of hydrochloric acid in the mixture at the particle level, due to the ease with which it diffuses through the bornite particles, achieving greater penetration of the pre-treatment.

Se cuantificaron, analizaron y compararon propiedades físicas de tres diluyentes (Shellsol, Orfom y Escaid) utilizados en extracción por solvente de cobre y una solución sintética de lixiviación de minerales de cobre (PLS) con una concentración representativa de hierro y cobre. Las propiedades analizadas fueron densidad, viscosidad y tensión Interfacial, además se evaluó el efecto del porcentaje de extractante (porcentaje de extractante presente en la fase organica expresada en volumen/volumen) (% v/v) en la fase organica sobre la densidad y la viscosidad. Las concentraciones de cobre y hierro en el PLS fueron de 4,5 [g/L] y 5,0 [g/L] respecivamente. Las temperaturas utilizadas fueron 25, 35 y 45 °C. Los resultados obtenidos muestran que la temperatura produce un efecto similar sobre la densidad de los diluyentes y PLS, obteniéndose una tendencia semejante en las curvas con leves variaciones; por su parte el efecto de la temperatura sobre la viscosidad presenta las mayores diferencias entre los diluyentes y PLS. La variación del porcentaje de extractante (%v/v) en la fase orgánica a temperatura constante, produce una leve variación de la densidad presentando tendencias similares para los tres diluyentes; mientras que los mayores efectos se ven reflejados en la viscosidad, mostrando tendencias semejantes en las tres curvas.Palabras claves: Extracción por solvente, diluyente, porcentaje de extractante, densidad, viscosidad.