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The authors wish to make the following corrections to this paper
David Torres; Luís Ayala; Ricardo I. Jeldres; Eduardo Cerecedo-Sáenz; Eleazar Salinas-Rodríguez; Pedro Robles; Norman Toro. Correction: Torres et al. Leaching Chalcopyrite with High MnO2 and Chloride Concentrations. Metals 2020, 10, 107. Metals 2021, 11, 1312 .
AMA StyleDavid Torres, Luís Ayala, Ricardo I. Jeldres, Eduardo Cerecedo-Sáenz, Eleazar Salinas-Rodríguez, Pedro Robles, Norman Toro. Correction: Torres et al. Leaching Chalcopyrite with High MnO2 and Chloride Concentrations. Metals 2020, 10, 107. Metals. 2021; 11 (8):1312.
Chicago/Turabian StyleDavid Torres; Luís Ayala; Ricardo I. Jeldres; Eduardo Cerecedo-Sáenz; Eleazar Salinas-Rodríguez; Pedro Robles; Norman Toro. 2021. "Correction: Torres et al. Leaching Chalcopyrite with High MnO2 and Chloride Concentrations. Metals 2020, 10, 107." Metals 11, no. 8: 1312.
A simple criterion is proposed to quantitatively estimate the resistance of aggregates based on incremental mechanical shear disturbances. Aggregate strength can be affected by the hydrodynamic conditions under which flocculation occurs; therefore, an experimental method is standardized to determine the resistance of aggregate structures that are formed under defined conditions of salinity (NaCl 0–0.1 M), mixing time (3 min), and mean shear rate (G = 273 s−1). Kaolin particles were flocculated in saline solutions with an anionic flocculant of high molecular weight. The method involves increasing the mean shear rate (G = 0–1516 s−1). Each increment represents a new experiment that starts from the base of 273 s−1. Target aggregates are increasingly fragmented as mechanical disturbance increases. The monotonic relationship between the mean shear rate increments (ΔG) and the final size of the aggregates is used for a quantitative estimate of the resistance of the target aggregates since this resistance underlies this relationship. The evolution of aggregate size is analyzed by the Focused Beam Reflectance Measurement (FBRM) method, which may capture the chord length distribution on concentrated slurries. To estimate and compare the resistance of the target aggregates in solutions with different salinities, a pseudo-first-order model that describes the rupture degree as a function of shear rate increments obtains the characteristic shear rate. The rupture percentage is reached with considerably lower agitation increments at higher salinity than at low salinity. This criterion is expected to help improve the efficiency of solid–liquid separation processes, especially in plants operating with seawater, be it raw or partially desalinated.
Matías Jeldres; Luis Ayala; Pedro Robles; Edelmira Gálvez; Williams Leiva; Pedro Toledo; Ricardo Jeldres. A Criterion for Estimating the Strength of Flocculated Aggregates in Salt Solutions. Minerals 2021, 11, 713 .
AMA StyleMatías Jeldres, Luis Ayala, Pedro Robles, Edelmira Gálvez, Williams Leiva, Pedro Toledo, Ricardo Jeldres. A Criterion for Estimating the Strength of Flocculated Aggregates in Salt Solutions. Minerals. 2021; 11 (7):713.
Chicago/Turabian StyleMatías Jeldres; Luis Ayala; Pedro Robles; Edelmira Gálvez; Williams Leiva; Pedro Toledo; Ricardo Jeldres. 2021. "A Criterion for Estimating the Strength of Flocculated Aggregates in Salt Solutions." Minerals 11, no. 7: 713.
The authors wish to make the following corrections to this paper
David Torres; Luís Ayala; Manuel Saldaña; Manuel Cánovas; Ricardo I. Jeldres; Steven Nieto; Jonathan Castillo; Pedro Robles; Norman Toro. Correction: Torres, D. et al. Leaching Manganese Nodules in an Acid Medium and Room Temperature Comparing the Use of Different Fe Reducing Agents. Metals 2019, 9, 1316. Metals 2020, 10, 506 .
AMA StyleDavid Torres, Luís Ayala, Manuel Saldaña, Manuel Cánovas, Ricardo I. Jeldres, Steven Nieto, Jonathan Castillo, Pedro Robles, Norman Toro. Correction: Torres, D. et al. Leaching Manganese Nodules in an Acid Medium and Room Temperature Comparing the Use of Different Fe Reducing Agents. Metals 2019, 9, 1316. Metals. 2020; 10 (4):506.
Chicago/Turabian StyleDavid Torres; Luís Ayala; Manuel Saldaña; Manuel Cánovas; Ricardo I. Jeldres; Steven Nieto; Jonathan Castillo; Pedro Robles; Norman Toro. 2020. "Correction: Torres, D. et al. Leaching Manganese Nodules in an Acid Medium and Room Temperature Comparing the Use of Different Fe Reducing Agents. Metals 2019, 9, 1316." Metals 10, no. 4: 506.
A population balance model (PBM) is used to describe flocculation of particle tailings in seawater at pH 8 for a range of mixing intensities. The size of the aggregates is represented by the mean chord length, determined by the focused beam reflectance measurement (FBRM) technique. The PBM follows the dynamics of aggregation and breakage processes underlying flocculation and provides a good approximation to the temporal evolution of aggregate size. The structure of the aggregates during flocculation is described by a constant or time-dependent fractal dimension. The results revealed that the compensations between the aggregation and breakage rates lead to a correct representation of the flocculation kinetics of the tailings of particles in seawater and, in addition, that the representation of the flocculation kinetics in optimal conditions is equally good with a constant or variable fractal dimension. The aggregation and breakage functions and their corresponding parameters are sensitive to the choice of the fractal dimension of the aggregates, whether constant or time dependent, however, under optimal conditions, a constant fractal dimension is sufficient. The model is robust and predictive with a few parameters and can be used to find the optimal flocculation conditions at different mixing intensities, and the optimal flocculation time can be used for a cost-effective evaluation of the quality of the flocculant used.
Gonzalo R. Quezada; Luís Ayala; Williams H. Leiva; Norman Toro; Pedro G. Toledo; Pedro Robles; Ricardo I. Jeldres. Describing Mining Tailing Flocculation in Seawater by Population Balance Models: Effect of Mixing Intensity. Metals 2020, 10, 240 .
AMA StyleGonzalo R. Quezada, Luís Ayala, Williams H. Leiva, Norman Toro, Pedro G. Toledo, Pedro Robles, Ricardo I. Jeldres. Describing Mining Tailing Flocculation in Seawater by Population Balance Models: Effect of Mixing Intensity. Metals. 2020; 10 (2):240.
Chicago/Turabian StyleGonzalo R. Quezada; Luís Ayala; Williams H. Leiva; Norman Toro; Pedro G. Toledo; Pedro Robles; Ricardo I. Jeldres. 2020. "Describing Mining Tailing Flocculation in Seawater by Population Balance Models: Effect of Mixing Intensity." Metals 10, no. 2: 240.
The unique properties of ionic liquids (ILs) drive the growing number of novel applications in different industries. The main features of ILs are high thermal stability, recyclability, low flash point, and low vapor pressure. This study investigated pure chalcopyrite dissolution in the presence of the ionic liquid 1-butyl-3-methylimidazolium hydrogen sulfate, [BMIm]HSO4, and a bromide-like complexing agent. The proposed system was compared with acid leaching in sulfate media with the addition of chloride and bromide ions. The results demonstrated that the use of ionic liquid and bromide ions improved the chalcopyrite leaching performance. The best operational conditions were at a temperature of 90 °C, with an ionic liquid concentration of 20% and 100 g/L of bromide.
Marcelo Rodríguez; Luís Ayala; Pedro Robles; Rossana Sepúlveda; David Torres; Francisco Raul Carrillo-Pedroza; Ricardo I. Jeldres; Norman Toro. Leaching Chalcopyrite with an Imidazolium-Based Ionic Liquid and Bromide. Metals 2020, 10, 183 .
AMA StyleMarcelo Rodríguez, Luís Ayala, Pedro Robles, Rossana Sepúlveda, David Torres, Francisco Raul Carrillo-Pedroza, Ricardo I. Jeldres, Norman Toro. Leaching Chalcopyrite with an Imidazolium-Based Ionic Liquid and Bromide. Metals. 2020; 10 (2):183.
Chicago/Turabian StyleMarcelo Rodríguez; Luís Ayala; Pedro Robles; Rossana Sepúlveda; David Torres; Francisco Raul Carrillo-Pedroza; Ricardo I. Jeldres; Norman Toro. 2020. "Leaching Chalcopyrite with an Imidazolium-Based Ionic Liquid and Bromide." Metals 10, no. 2: 183.
Most copper minerals are found as sulfides, with chalcopyrite being the most abundant. However; this ore is refractory to conventional hydrometallurgical methods, so it has been historically exploited through froth flotation, followed by smelting operations. This implies that the processing involves polluting activities, either by the formation of tailings dams and the emission of large amounts of SO2 into the atmosphere. Given the increasing environmental restrictions, it is necessary to consider new processing strategies, which are compatible with the environment, and, if feasible, combine the reuse of industrial waste. In the present research, the dissolution of pure chalcopyrite was studied considering the use of MnO2 and wastewater with a high chloride content. Fine particles (−20 µm) generated an increase in extraction of copper from the mineral. Besides, it was discovered that working at high temperatures (80 °C); the large concentrations of MnO2 become irrelevant. The biggest copper extractions of this work (71%) were achieved when operating at 80 °C; particle size of −47 + 38 µm, MnO2/CuFeS2 ratio of 5/1, and 1 mol/L of H2SO4.
David Torres; Luís Ayala; Ricardo I. Jeldres; Eduardo Cerecedo-Sáenz; Eleazar Salinas-Rodríguez; Pedro Robles; Norman Toro. Leaching Chalcopyrite with High MnO2 and Chloride Concentrations. Metals 2020, 10, 107 .
AMA StyleDavid Torres, Luís Ayala, Ricardo I. Jeldres, Eduardo Cerecedo-Sáenz, Eleazar Salinas-Rodríguez, Pedro Robles, Norman Toro. Leaching Chalcopyrite with High MnO2 and Chloride Concentrations. Metals. 2020; 10 (1):107.
Chicago/Turabian StyleDavid Torres; Luís Ayala; Ricardo I. Jeldres; Eduardo Cerecedo-Sáenz; Eleazar Salinas-Rodríguez; Pedro Robles; Norman Toro. 2020. "Leaching Chalcopyrite with High MnO2 and Chloride Concentrations." Metals 10, no. 1: 107.
The deposits of Fe-Mn, in the seabed of the planet, are a good alternative source for the extraction of elements of interest. Among these are marine nodules, which have approximately 24% manganese and may be a solution to the shortage of high-grade ores on the surface. In this investigation, an ANOVA analysis was performed to evaluate the time independent variables and MnO2/reducing agent in the leaching of manganese nodules with the use of different Fe reducing agents (FeS2, Fe2+, Fe0 and Fe2O3). Tests were also carried out for the different reducing agents evaluating the MnO2/Fe ratio, in which the Fe0 (FeC) proved to be the best reducing agent for the dissolution of Mn from marine nodules, achieving solutions of 97% in 20 min. In addition, it was discovered that at low MnO2/Fe ratios the acid concentration in the system is not very relevant and the potential and pH were in ranges of −0.4–1.4 V and −2–0.1 favoring the dissolution of Mn from MnO2.
David Torres; Luís Ayala; Manuel Saldaña; Manuel Cánovas; Ricardo I. Jeldres; Steven Nieto; Jonathan Castillo; Pedro Robles; Norman Toro. Leaching Manganese Nodules in an Acid Medium and Room Temperature Comparing the Use of Different Fe Reducing Agents. Metals 2019, 9, 1316 .
AMA StyleDavid Torres, Luís Ayala, Manuel Saldaña, Manuel Cánovas, Ricardo I. Jeldres, Steven Nieto, Jonathan Castillo, Pedro Robles, Norman Toro. Leaching Manganese Nodules in an Acid Medium and Room Temperature Comparing the Use of Different Fe Reducing Agents. Metals. 2019; 9 (12):1316.
Chicago/Turabian StyleDavid Torres; Luís Ayala; Manuel Saldaña; Manuel Cánovas; Ricardo I. Jeldres; Steven Nieto; Jonathan Castillo; Pedro Robles; Norman Toro. 2019. "Leaching Manganese Nodules in an Acid Medium and Room Temperature Comparing the Use of Different Fe Reducing Agents." Metals 9, no. 12: 1316.