The pregnant leach solution (PLS) obtained when 10 g/L goldfieldite ore was leached using 1.7 mol/L ammonia solution at 75 °C within 120 min was employed for solvent extraction tests. This PLS obtained at established conditions was made of 571.27 mg/L Cu 2+, 31.4 mg/L Fe 3+, 5.09 mg/L Pb 2+, and 3.55 mg/L Ca 2+, respectively [ 18 ].

Paper No. 487. AMMONIA LEACHING IN THE COPPER INDUSTRY: A REVIEW. V Radmehr1, S M J Koleini2,*, M R Khalesi3 and M R Tavakoli Mohammadi4. …

This study presents the novel idea of a cyanide-free leaching method, i.e., glycine-ammonia leaching in the presence of permanganate, to treat a low-grade and copper-bearing gold tailing. Ammonia played a key role as a pH modifier, lixiviant and potential catalyst (as cupric ammine) in this study. Replacing ammonia with other pH …

The leaching kinetics of low-grade copper ore with high-alkality gangues was studied in ammonia-ammonium sulphate solution. The main parameters, such as ammonia and ammonium sulphate concentrations, particle size, solid-to-liquid ratio and reaction temperature, were chosen in the experiments. The results show that the increase of …

Use of Ammonia Salts in Selective Copper Extraction from Tailings. M. Deniz Turan1&Ramazan Orhan2&Mücevher Turan3&Hasan Nizamoğlu1. Received: 7 October …

The leaching of copper from the tailings of Baifang Copper Mine in Hunan province in China by aqueous ammonia/ammonium chloride solutions has been studied. The …

By addition of Fig. 3 Ammonia leaching of tailings (leaching time 120 min, solid/liquid ammonia and oxygen, metallic copper and copper oxides are ratio 1/10, a 20 °C; b 30 °C; c 40 °C; d 50 °C; e 60 °C) Mining, Metallurgy & Exploration As seen in the figure, with the increased concentration of ammonium hydroxide, there was a significant ...

The leaching tests were performed at room temperature (about 20 ± 3 °C), during 48 h, in Erlenmeyer flasks, using 10 g of sample and a solid (L/S) ratio of 20 (v/w), 2 times the stoichiometric amount of ammonia required to dissolve copper, 2.5 mol dm −3 /2 mol dm −3 for ammonia/ammonium sulphate molar ratio, 1 mol dm −3 hydrogen ...

The paper presents results of extraction of copper (II) from ammonia leach solutions. The effect of a type of extractant, its concentration and type of diluent in organic phase on extraction ...

The leaching of copper from the tailings of Baifang Copper Mine in Hunan province in China by aqueous ammonia/ammonium chloride solutions has been studied. The tailings belong to a low-grade and high-alkaline copper ore. The effect of leaching time, the concentration of ammonia, solid/liquid ratio and temperature were investigated. The …

ammonia/ (ammonium chloride leaching time, the concentration of ammonia, solid/liquid ratio and temperature 75 Guo-dong and Qing, 2010) Dissolution kinetics of low grade complex copper ore in ...

A comparison leaching with alkaline bacteria, ammonia or a combination of the two clearly indicated that copper recovery was remarkably better with combination that Cu extraction rate increased from 4.42% (48 days, ammonia leaching) or approximately 20% (30 days, alkaline bacterial leaching) to 29.57% (30 days, combined leaching).

According to the pH (pH= 9.26 + log ([N H 3]/[N H 4 +]) of the ammonia-ammonium system, the pH of the ammonia solution was determined by the proportion of NH 3 to NH 4 + [31]. Therefore, the addition of a third component might affect the pH of the ammonia system, which would promote the formation of nickel-ammonia and cobalt …

Optimum leaching conditions from malachite ore by ammonia/ammonium carbonate solution are found as ammonia/ammonium carbonate concentrations: 5 M NH4OH+0.3 M (NH4)2CO3; solid/liquid ratio: 1:10 g ...

The use of ammonia, ammonium sulphate, and ammonium chloride in the extraction of copper from chalcopyrite ores has gained enormous attention to acidic media as a result of solving the setbacks of acid consumption, low cost, and ease of regeneration . The influences of important parameters such as lixiviant concentration, reaction …

Leaching of copper from tailings using ammonia–ammonium chloride solution and its dynamics Ammonia– ammonium chloride Leaching time, the concentration of ammonia, solid/ liquid ratio and ...

The leachate can be directly used to produce CaCO 3, and NH 4 Cl can be reused multiple times (Konopacka-Łyskawa et al., 2017). This study pretreated high-calcium gold …

In 2008, Antonijevic proposed copper recovery from Bor copper mine tailings through acid leaching. The tailings had around 21% sulfide content and 0.2% copper, with a particle size of approximately 0.074 mm. He used a 1-L beaker with mechanical and magnetic agitators, employing 500 mL of leaching solution and 100 g …

The initial content of copper in the tailings was 1109 mg Cu/kg of dry tailing, where close to 40% of the sample in weight corresponded to a soluble fraction. ... the technique envisaged consists in the copper …

The solubilities of copper hydroxide Cu(OH) 2, copper oxide CuO, atacamite Cu(OH) 1.5 Cl 0.5, malachite Cu 2 (OH) 2 CO 3 and chessylite Cu 3 (OH) 2 (CO 3) 2 in an ammonia-ammonium chloride-water solution were calculated using an exponential computation method based on both mass balance and charge balance equations. The …

4OH (64%)>NH. 4Cl (42%)>NH. 4NO. 3(40%). The highest copper extraction efficiency was obtained in the leaching process that was conducted with the solutions obtained by mixing ammonia salts in the best conditions. Accordingly, as a result of 6 h of leaching at 30 °C in the presence of 22.5% NH. 4OH and 100 g/L (NH.

ammonia/ammonium chloride solution and its dynamics ammonia/ (ammonium chloride leaching time, the concentration of ammonia, solid/liquid ratio and temperature 75 Guo-dong and Qing, 2010 ...

The leaching kinetics of willemite in ammonia-ammonium chloride solution was investigated. The effects of the ammonia-ammonium ratio, particle size, temperature, and total ammonia concentration on the leaching rate of willemite were determined. The results show that the optimum ammonia-ammonium ratio is 1:2 over …

The leaching kinetics of Tang-dan refractory low grade complex copper ore was investigated in ammonia-ammonium chloride solution. The concentration of ammonia and ammonium chloride, the ore particle size, the solid-to-liquid ratio and the temperature were chosen as parameters in the experiments. The results show that …

Abstract Ammoniacal leaching and sulfuric acid leaching were explored separately to recover copper from smelter slag. The overall 75% copper recovery was achieved from the smelter slag under optimum condition using ammoniacal leaching. The low copper recovery in this process is directly related to the complex slag mineralogy …

The predicted and experimental results indicate that the precipitate CuO limits the copper solubility in aqueous ammonia and Cu(OH)1.5Cl0.5 in aqueous …

Ammonia is known to be an effective leaching agent in hydrometallurgical processes. Despite being initially used to selectively extract Cu, ammoniacal leaching has been expanded towards a range of other non-ferrous metals, e.g., Zn, Ni, Co, Ag, and Au [1,2,3,4,5].The performance of ammoniacal metal extraction systems is determined by …

The highest copper extraction efficiency was obtained in the leaching process that was conducted with the solutions obtained by mixing ammonia salts in the best conditions. Accordingly, as a ...

Fig. 1 shows that the most critical variable was the solid concentration in the leaching solution, wherein the copper extraction rate increased by 23% (for similar pH values and NH 3 level). This coincides with several investigations, which showed that the lower the S/L ratio, the higher the kinetics of copper dissolution. The more significant …

CCD was performed to optimize molybdenum yield by leaching roasted molybdenite using an ammonia–ammonium nitrate solution. Two factors were considered in the trial planning: ammonium nitrate concentration (A) and ammonia concentration (B), as given in Table 1. Trials were designed utilizing design expert 10.0.0 …

Copper Leaching - Free download as PDF File (.pdf), Text File (.txt) or read online for free. effect of copper leaching to the environment

The experiments of agitation leaching were carried out in aqueous ammonia/ammonium carbonate solution, to recover copper from the flotation tailings of waste copper oxide residue. The main copper minerals contained in the flotation tailings are chrysocolla, malachite, and cuprite, with the copper grade of 1.12%. Effects of lixiviant concentration, …

From the Henderson-Hasslebach equation (Equation (10)), it can be indicated that the pH of the solution controls the ammonia concentration.Therefore, ammonia (NH 3) concentration is determined from the total ammonia concentration Equation (11) and the solution pH according to Equation (10).At low pH, greater amount of the total ammonia …

This study presents the novel idea of a cyanide-free leaching method, i.e., glycine–ammonia leaching in the presence of permanganate, to treat a low-grade and copper-bearing gold tailing.

A new process of producing zinc from zinc oxide ores in the system of NH_4Cl-NH_3-H_2O was introduced . In the process, NH_4Cl-NH_3-H_2O was used as leaching agent, the Zn(NH_3)~(2+)_i was formed when the solution was reacted with zinc oxide ores, the rate of zinc that could be dissolved in the solution was more than 93%, while the content of …

Ammonia medium used for leaching was prepared by adding 66 g of ammonium sulphate to 3.5 mL ammonium solution and 200 mL of distilled water. Half of the prepared ammonia solution was used to leach 40 g of the copper tailings sample. The pH during the entire leaching process was 8.3.