scholarly journals Cupric and Chloride Ions: Leaching of Chalcopyrite Concentrate with Low Chloride Concentration Media

Minerals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 639 ◽  
Author(s):  
Cynthia M. Torres ◽  
Yousef Ghorbani ◽  
Pía C. Hernández ◽  
Francisca J. Justel ◽  
Matías I. Aravena ◽  
...  
Keyword(s):  
Chloride Concentration ◽  
Xrd Analysis ◽  
Formation Constants ◽  
Chloride Ions ◽  
Chloro Complex ◽  
Copper Extraction ◽  
Chloro Complexes ◽  
Complex Species ◽  
Leaching Solution ◽  
Chalcopyrite Concentrate

In this paper, the effect of the cupric and chloride ions concentrations on copper dissolution from chalcopyrite concentrate was studied in acidified media. Variables included three different concentrations of Cu2+ (0.5, 1.5, and 2.5 g L−1), four different concentrations of Cl− (0, 5, 7, and 10 g L−1), two different pH values of 1 and 2, and a constant temperature of 60 °C. Results indicated that addition of Cl− to the system improves copper extractions, especially at higher concentrations of Cu2+. Initial copper concentrations in the leaching solution did not significantly affect the copper extraction when Cl− was not present. Better copper extractions were obtained at pH 1 as compared with pH 2. As the Cu2+ and Cl− concentrations were increased, higher values of redox potential were obtained. According to the formation constants of the chloro-complexes, the predominant species in the Cu2+/Cl− system in the studied interval were CuCl+ and Cu2+. Using a model of copper speciation in the experimental range predicted for a single copper concentration with increasing Cl− concentration, the Cu2+ concentration decreased significantly while the concentration of the chloro-complex species CuCl+ increased. In the leached residue, evidence of sulfur formation was found using SEM and corroborated by XRD analysis. When chloride is present in the medium, the amounts of copper and iron in the residue decrease, confirming a positive effect of chloride on the extraction of copper from concentrate for the studied conditions.

scholarly journals Leaching of Pure Chalcocite in a Chloride Media Using Waste Water at High Temperature

Metals ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 384
Author(s):  
Kevin Pérez ◽  
Ricardo I. Jeldres ◽  
Steven Nieto ◽  
Eleazar Salinas-Rodríguez ◽  
Pedro Robles ◽  
...  
Keyword(s):  
Chloride Concentration ◽  
Chloride Ion ◽  
Xrd Analysis ◽  
Chloride Ions ◽  
Common Mechanism ◽  
Copper Extraction ◽  
X Ray Diffraction ◽  
Kinetics Of Dissolution ◽  
Main Component ◽  
Two Stages

Studying the dissolution of chalcocite allows to understand the behavior of the most abundant secondary sulfide ore in copper deposits, while digenite (Cu1.8S) and other intermediate sulfides (Cu2−xS) are often associated with chalcocite. The most common mechanism of dissolution is by two stages, and chloride ions benefit the kinetics of dissolution. In this study, a pure chalcocite mineral (99.9% according to XRD (X-Ray Diffraction) analysis) is leached in chloride media using NaCl and wastewater as the sources of chloride. Magnetic leaching tests are performed at 65, 75, and 95 °C, using a particle size between −150 and + 106 μm. Chloride concentration and leaching time are the main variables. A substantial dissolution of chalcocite was obtained with 0.5 M H2SO4, 100 g/L of chloride and a leaching time of 3 h. The apparent activation energy (Ea) derived from the slopes of the Arrhenius plots was 36 kJ/mol. The XRD analysis proves the presence of elemental sulfur (S0) as the main component in the leaching residue. No significant differences in copper extraction were detected when using 100 g/L of chloride ion or wastewater (39 g/L).

scholarly journals Effects of Fe+2 and Fe+3 in Pretreatment and Leaching on a Mixed Copper Ore in Chloride Media

Metals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 866
Author(s):  
María E. Taboada ◽  
Pía C. Hernández ◽  
Aldo P. Padilla ◽  
Nathalie E. Jamett ◽  
Teófilo A. Graber
Keyword(s):  
Chloride Concentration ◽  
Solution Concentration ◽  
Copper Extraction ◽  
Curing Time ◽  
Ferrous Ions ◽  
Copper Ore ◽  
Second Stage ◽  
Acid Consumption ◽  
Nacl Concentration ◽  
Leaching Solution

A study of the pretreatment stage and subsequent leaching of a mixed copper ore with different chloride solutions containing iron was carried out. The first stage considered pretreatment tests to decide the best conditions. Two levels of each factor were analyzed, 20 and 50 kg/t of NaCl, 17 and 25 kg/t of H2SO4, 0 and 25 kg/t of Fe2(SO4)3·9.2H2O, 0 and 25 kg/t of Fe2SO4·7H2O, and a curing time of 15 and 30 days. The results showed a significant effect of NaCl and curing time on the extraction, and less effect was found with the variation of acid and iron salts. The second stage included column leaching using a solution with 0.5 g/L of Cu+2, 80 g/L of Cl−, 10 g/L of H2SO4, and variable concentrations of ferric and ferrous ions (0 and 2 g/L). The best copper extraction of 80.2% was found considering a pretreatment of 30 days, 25 kg/t of H2SO4, 50 kg/t of NaCl, and a leaching solution concentration described previously with 2 g/L of Fe+2. The results showed the leaching of all copper oxide species and 20% of the copper sulfide species. In addition, there was a reduction in the acid consumption as the resting time increases. Furthermore, to evaluate a possible decrease in time and acid in pretreatment and chloride in leaching, tests including 10 and 25 kg/t of H2SO4 and 1, 15, and 30 days of curing and a diminution of the NaCl concentration to 20 g/L (content from seawater) were executed. The results showed a significant effect on curing time below 15 days. Furthermore, the slight influence of the decrease of acid on copper extraction gives cost reduction opportunities. The diminution of chloride concentration (80 to 20 g/L) in leaching solution decreases the extraction from 79% to 66.5%. Finally, the Mellado leaching kinetic model was successfully implemented.

scholarly journals Use of Seawater/Brine and Caliche’s Salts as Clean and Environmentally Friendly Sources of Chloride and Nitrate Ions for Chalcopyrite Concentrate Leaching

Minerals ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 477 ◽  
Author(s):  
Pía Hernández ◽  
Alexis Dorador ◽  
Monserrat Martínez ◽  
Norman Toro ◽  
Jonathan Castillo ◽  
...  
Keyword(s):  
Sulfuric Acid Concentration ◽  
Chloride Concentration ◽  
Cost Effective ◽  
Copper Extraction ◽  
Distilled Water ◽  
Sample Type ◽  
Nitrate Ions ◽  
Cost Effective Alternative ◽  
Chalcopyrite Concentrate ◽  
Pre Treatment

A less harmful approach for the environment regarding chalcopyrite concentrate leaching, using seawater/brine and caliche’s salts as a source of chloride and nitrate ions, was investigated. Different variables were evaluated: sulfuric acid concentration, sodium nitrate concentration, chloride concentration, source of water (distilled water, seawater, and brine), temperature, concentrate sample type, nitrate source (analytical grade and industrial salt), and pre-treatment methods in order to obtain maximum copper extraction. All tests were performed at moderate temperatures (≤45 °C) and atmospheric pressure. The leaching system using distilled water, seawater, and brine base media resulted in copper extraction of 70.9%, 90.6%, and 86.6% respectively. The leaching media, with a concentration of 20 g/L Cl−, obtained a maximum Cu extraction of 93.5%. An increase in the concentration of H2SO4 and NaNO3 from 0.5 to 0.7 M, led to an increase in the copper extraction. The use of an industrial salt compared to the analytical salt did not show great variations in the percentage of extraction achieved, which would be a good and cost effective alternative. The increase in temperature from 25 to 45 °C showed a great effect on the copper leaching (of 60% until 90.6%, respectively). The pre-treatment is suggested to increase copper extraction from 60.0% to 71.4%.

scholarly journals Leaching of Pure Chalcocite in a Chloride Media Using Sea Water and Waste Water

Metals ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 780 ◽  
Author(s):  
Norman Toro ◽  
Williams Briceño ◽  
Kevin Pérez ◽  
Manuel Cánovas ◽  
Emilio Trigueros ◽  
...  
Keyword(s):  
Sea Water ◽  
Chloride Concentration ◽  
Xrd Analysis ◽  
Quadratic Model ◽  
Copper Extraction ◽  
Copper Ore ◽  
Copper Dissolution ◽  
Rapid Dissolution ◽  
Chloride Environment ◽  
Kinetics Of

Chalcocite is the most important and abundant secondary copper ore in the world with a rapid dissolution of copper in an acid-chloride environment. In this investigation, the methodology of surface optimization will be applied to evaluate the effect of three independent variables (time, concentration of sulfuric acid and chloride concentration) in the leaching of pure chalcocite to extract the copper with the objective of obtaining a quadratic model that allows us to predict the extraction of copper. The kinetics of copper dissolution in regard to the function of temperature is also analyzed. An ANOVA indicates that the linear variables with the greatest influence are time and the chloride concentration. Also, the concentration of chloride-time exerts a significant synergic effect in the quadratic model. The ANOVA indicates that the quadratic model is representative and the R2 value of 0.92 is valid. The highest copper extraction (67.75%) was obtained at 48 h leaching under conditions of 2 mol/L H2SO4 and 100 g/L chloride. The XRD analysis shows the formation of a stable and non-polluting residue; such as elemental sulfur (S0). This residue was obtained in a leaching time of 4 h at room temperature under conditions of 0.5 mol/L H2SO4 and 50 g/L Cl−.

Investigating and Optimization of Copper Extraction from Chalcopyrite Concentrate with Hydrogen Peroxide in Presence of Acetic Acid

2017 ◽  
Vol 7 (4) ◽  
Author(s):  
Mehmat Deniz Turan ◽  
Musa Sarikaya ◽  
Z. Abidin Sari ◽  
Ahmet Haxhiaj ◽  
Tolga Depci ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Acetic Acid ◽  
Copper Extraction ◽  
Chalcopyrite Concentrate

Selectivity coefficients of some simple and complex inorganic ions for Spheron DEAE

1984 ◽  
Vol 49 (10) ◽  
pp. 2349-2354 ◽  
Author(s):  
František Vláčil ◽  
Karel Koňák
Keyword(s):  
Ion Exchange ◽  
Mobile Phase ◽  
Dynamic Method ◽  
Precious Metals ◽  
Inorganic Ions ◽  
Chromatographic Determination ◽  
Chloride Ions ◽  
Chloro Complexes ◽  
Selectivity Coefficients

The selectivity coefficients of the nitrate and chloride ions and of anionic chloro complexes of Au(III), Rh(III), Pd(II), and Pt(IV) for ion exchange on Spheron DEAE in the chloride form are determined by the dynamic method. the complex anion species formed are identified and the ion exchange nature of the sorption of precious metals on this sorbent is confirmed based on the elution order of the precious metals as determined previously by the column chromatography on Spheron DEAE using hydrochloric acid as the mobile phase. The effect of the presence of perchlorate in the mobile phase during the liquid chromatography of precious metals and during the chromatographic determination of nitrate traces is explained.

Characterization and A Preliminary Study of TiO2 Synthesis from Lampung Iron Sand

2020 ◽  
Vol 849 ◽  
pp. 113-118
Author(s):  
Yayat Iman Supriyatna ◽  
Slamet Sumardi ◽  
Widi Astuti ◽  
Athessia N. Nainggolan ◽  
Ajeng W. Ismail ◽  
...  
Keyword(s):  
Food Packaging ◽  
Xrd Analysis ◽  
Major Elements ◽  
Raw Material ◽  
Solid Residue ◽  
X Ray Diffraction ◽  
X Ray ◽  
Leaching Solution ◽  
Ti Content

The purpose of this study is to characterize Lampung iron sand and to conduct preliminary experiments on the TiO2 synthesis which can be used for the manufacturing of functional food packaging. The iron sand from South Lampung Regency, Lampung Province that will be utilized as raw material. The experiment was initiated by sieving the iron sand on 80, 100, 150, 200 and 325 mesh sieves. Analysis using X-Ray Fluorescence (XRF) to determine the element content and X-Ray Diffraction (XRD) to observe the mineralization of the iron sand was conducted. The experiment was carried out through the stages of leaching, precipitation, and calcination. Roasting was applied firstly by putting the iron sand into the muffle furnace for 5 hours at a temperature of 700°C. Followed by leaching using HCl for 48 hours and heated at 105°C with a stirring speed of 300 rpm. The leaching solution was filtered with filtrate and solid residue as products. The solid residue was then leached using 10% H2O2 solution. The leached filtrate was heated at 105°C for 40 minutes resulting TiO2 precipitates (powder). Further, the powder was calcined and characterized. Characterization of raw material using XRF shows the major elements of Fe, Ti, Mg, Si, Al and Ca. The highest Ti content is found in mesh 200 with 9.6%, while iron content is about 80.7%. While from the XRD analysis, it shows five mineral types namely magnetite (Fe3O4), Rhodonite (Mn, Fe, Mg, Ca) SiO3, Quart (SiO2), Ilmenite (FeOTiO2) and Rutile (TiO2). The preliminary experiment showed that the Ti content in the synthesized TiO2 powder is 21.2%. The purity of TiO2 is low due to the presence of Fe metal which is dissolved during leaching, so that prior to precipitation purification is needed to remove impurities such as iron and other metals.

Formation Constants of Copper(II) and Zinc(II) with N-salicylideneanthranilic Acid in 50–50 Water–dioxane

1972 ◽  
Vol 50 (10) ◽  
pp. 1609-1611
Author(s):  
R. K. Mehta ◽  
R K Gupta
Keyword(s):  
Sodium Perchlorate ◽  
Formation Constants ◽  
Protonation Constants ◽  
Fair Agreement ◽  
Complex Species ◽  
Color Changes

Protonation constants of N-salicylideneanthranilic acid and formation constants of its Cu(II) and Zn(II)complexes have been studied potentiometrically in 50% dioxane (vol/vol) solutions (μ = 0.1 sodium perchlorate) at 30 ± 0.2 °C. The color changes observed during titrations have been related to the formation of different complex species in solution. The formation constants are in fair agreement with the Irving and Williams rule.

scholarly journals Application of Novel Machine Learning Techniques for Predicting the Surface Chloride Concentration in Concrete Containing Waste Material

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2297
Author(s):  
Ayaz Ahmad ◽  
Furqan Farooq ◽  
Krzysztof Adam Ostrowski ◽  
Klaudia Śliwa-Wieczorek ◽  
Slawomir Czarnecki
Keyword(s):  
Machine Learning ◽  
Mean Square Error ◽  
Gene Expression Programming ◽  
Chloride Concentration ◽  
Absolute Error ◽  
Chloride Ions ◽  
Machine Learning Techniques ◽  
Extensive Literature ◽  
Mean Square ◽  
Chloride Concentrations

Structures located on the coast are subjected to the long-term influence of chloride ions, which cause the corrosion of steel reinforcements in concrete elements. This corrosion severely affects the performance of the elements and may shorten the lifespan of an entire structure. Even though experimental activities in laboratories might be a solution, they may also be problematic due to time and costs. Thus, the application of individual machine learning (ML) techniques has been investigated to predict surface chloride concentrations (Cc) in marine structures. For this purpose, the values of Cc in tidal, splash, and submerged zones were collected from an extensive literature survey and incorporated into the article. Gene expression programming (GEP), the decision tree (DT), and an artificial neural network (ANN) were used to predict the surface chloride concentrations, and the most accurate algorithm was then selected. The GEP model was the most accurate when compared to ANN and DT, which was confirmed by the high accuracy level of the K-fold cross-validation and linear correlation coefficient (R2), mean absolute error (MAE), mean square error (MSE), and root mean square error (RMSE) parameters. As is shown in the article, the proposed method is an effective and accurate way to predict the surface chloride concentration without the inconveniences of laboratory tests.

scholarly journals Effect of iron powder on copper extraction by acid leaching of chalcopyrite concentrate.

1996 ◽  
Vol 29 (4) ◽  
pp. 720-722 ◽  
Author(s):  
Ezequiel Cruz Sanchez ◽  
Yoshiaki Umetsu ◽  
Fumio Saito
Keyword(s):  
Iron Powder ◽  
Acid Leaching ◽  
Copper Extraction ◽  
Chalcopyrite Concentrate
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