Investigation of the possibility of copper recovery from the flotation tailings by acid leaching

Zinc-leaching residue (ZLR) is a strongly acidic hazardous waste; it has poor stability, high heavy metal levels, and releases toxic elements into the environment. ZLR has potential as a valuable resource, because it contains elevated levels of zinc and silver. In this paper, the recovery of zinc (Zn) and silver (Ag) from ZLR wastes from zinc hydrometallurgy workshops using water leaching followed by flotation was studied. During water leaching experiments, the zinc and copper recovery rates were 38% and 61%, respectively. Thereafter, various flotation testing parameters were optimized and included grinding time, reagent dosages, pulp density, flotation time, and type of adjuster. Experimental results demonstrated this flotation method successfully recycled Ag and Zn. A froth product containing more than 9256.41 g/t Ag and 12.26% Zn was produced from the ZLR with approximately 80.32% Ag and 42.88% Zn recoveries. The toxicity characteristic leaching procedure (TCLP) results indicated the water-leaching flotation process not only recycled valuable metals such as zinc and silver in zinc-containing hazardous wastes but lowered the hazardous waste levels to those of general wastes and recycled wastes in an efficient, economical, and environmentally friendly way.

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Optimization Studies on Recovery of Metals from Printed Circuit Board Waste

Bioinorganic Chemistry and Applications ◽

10.1155/2018/1067512 ◽

2018 ◽

Vol 2018 ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

P. Sivakumar ◽

D. Prabhakaran ◽

M. Thirumarimurugan

Keyword(s):

Printed Circuit Boards ◽

Printed Circuit Board ◽

Lead Nitrate ◽

Acid Leaching ◽

Circuit Board ◽

Copper Recovery ◽

Printed Circuit ◽

Waste Printed Circuit Boards ◽

Electrode Combination ◽

Lead Metal

The aim of the study was to recover copper and lead metal from waste printed circuit boards (PCBs). The electrowinning method is found to be an effective recycling process to recover copper and lead metal from printed circuit board wastes. In order to simplify the process with affordable equipment, a simple ammonical leaching operation method was adopted. The selected PCBs were incinerated into fine ash powder at 500°C for 1 hour in the pyrolysis reactor. Then, the fine ash powder was subjected to acid-leaching process to recover the metals with varying conditions like acid-base concentration, electrode combination, and leaching time. The relative electrolysis solution of 0.1 M lead nitrate for lead and 0.1 M copper sulphate for copper was used to extract metals from PCBs at room temperature. The amount of lead and copper extracted from the process was determined by an atomic absorption spectrophotometer, and results found were 73.29% and 82.17%, respectively. Further, the optimum conditions for the recovery of metals were determined by using RSM software. The results showed that the percentage of lead and copper recovery were 78.25% and 89.1% should be 4 hrs 10 A/dm2.

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Enhancement of copper recovery by acid leaching of high-mud copper oxides: A case study at Yangla Copper Mine, China

Journal of Cleaner Production ◽

10.1016/j.jclepro.2018.08.122 ◽

2018 ◽

Vol 202 ◽

pp. 321-331 ◽

Cited By ~ 11

Author(s):

Shenghua Yin ◽

Leiming Wang ◽

Aixiang Wu ◽

Michael L. Free ◽

Eugie Kabwe

Keyword(s):

Acid Leaching ◽

Copper Oxides ◽

Copper Recovery ◽

Copper Mine

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A Study of the Optimal Model of the Flotation Kinetics of Copper Slag from Copper Mine BOR

Archives of Mining Sciences ◽

10.2478/amsc-2014-0057 ◽

2014 ◽

Vol 59 (3) ◽

pp. 821-834 ◽

Cited By ~ 1

Author(s):

Rodoljub D. Stanojlović ◽

Jovica M. Sokolović

Keyword(s):

Pure Copper ◽

Copper Slag ◽

Copper Recovery ◽

Optimal Model ◽

Flotation Kinetics ◽

Kinetics Parameters ◽

Flotation Tailings ◽

Copper Mine ◽

Flotation Cell ◽

Kinetics Of

Abstract In this study the effect of mixtures of copper slag and flotation tailings from copper mine Bor, Serbia on the flotation results of copper recovery and flotation kinetics parameters in a batch flotation cell has been investigated. By simultaneous adding old flotation tailings in the ball mill at the rate of 9%, it is possible to increase copper recovery for about 20%. These results are compared with obtained copper recovery of pure copper slag. The results of batch flotation test were fitted by MatLab software for modeling the first-order flotation kinetics in order to determine kinetics parameters and define an optimal model of the flotation kinetics. Six kinetic models are tested on the batch flotation copper recovery against flotation time. All models showed good correlation, however the modified Kelsall model provided the best fit.

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Bioleaching of copper from old flotation tailings samples (Copper Mine Bor, Serbia)

Journal of the Serbian Chemical Society ◽

10.2298/jsc140411097s ◽

2015 ◽

Vol 80 (3) ◽

pp. 391-405 ◽

Cited By ~ 6

Author(s):

Srdjan Stankovic ◽

Ivana Moric ◽

Aleksandar Pavic ◽

Sandra Vojnovic ◽

Branka Vasiljevic ◽

...

Keyword(s):

Environmental Impact ◽

Acid Leaching ◽

Free Water ◽

Copper Extraction ◽

Acidic Water ◽

Acidic Lake ◽

Flotation Tailings ◽

Copper Mine

Bioleaching of samples taken from depths of 10, 15, and 20 meters from old flotation tailings of the Copper Mine Bor was conducted in shaken flasks using extremely acidic water of Lake Robuleas lixiviant. Yield of copper after five weeks of the bioleaching experiment was 68.34?1.21% for 15 m sample, 72.57?0.57% for 20 m sample and 97.78?5.50% for 10 m sample. The obtained results were compared to the results of acid leaching of the same samples and it was concluded that bioleaching was generally more efficient for the treatment of samples taken from depths of 10 m and 20 m. The content of pyrite in the 20 m sample, which contained the highest amount of this mineral, was reduced after bioleaching. Benefits of this approach are: recovery of substantial amounts of copper, reducing the environmental impact of flotation tailings and the application of abundant and free water from the Robule acidic lake as lixiviant. Results of the experiment showed that bioleaching can be more efficient than acid leaching for copper extraction from flotation tailings with higher sulfide contents.

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Investigation of the optimal technology for copper leaching from old flotation tailings of the copper mine bor (Serbia)

Metallurgical and Materials Engineering ◽

10.30544/514 ◽

2020 ◽

Vol 26 (2) ◽

pp. 209-222 ◽

Cited By ~ 1

Author(s):

Vesna Conić ◽

Srđan Stanković ◽

Branislav Marković ◽

Dragana Božić ◽

Jovica Stojanović ◽

...

Keyword(s):

Iron Concentration ◽

Copper Recovery ◽

Copper Extraction ◽

Efficient Technology ◽

Flotation Tailings ◽

Copper Mine ◽

Moderately Thermophilic ◽

Acidophilic Bacteria ◽

Leaching Experiment ◽

Optimal Technology

This work aimed to investigate optimal leaching technology for copper extraction from old flotation tailings of the Copper Mine Bor. The leaching degree of copper after leaching with sulphuric acid at 80 °C was 50%, the maximal leaching degree was achieved after 30 minutes. Then, old flotation tailings were leached with adapted moderately thermophilic acidophilic bacteria in a bioreactor at 40 °C. Maximal leaching degree of 84% was achieved after nine days of the experiment. The third leaching experiment was conducted with biogenic lixiviant obtained by bacterial oxidation of the ferrous iron (concentration of Fe3+ 1300 mgL-1, pH 2.14). Biogenic lixiviant with ferric sulphate was then used in the leaching experiment at 80 °C. Maximal leaching degree was 78%, and it was achieved after five minutes. Results of the leaching experiments show that the most efficient technology for copper recovery from the old flotation tailings of the Copper Mine Bor was leaching with biogenic lixiviant.

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Cobalt and copper recovery from the ancient flotation tailings by selective sulfation roast - leaching process

Journal of Mining and Metallurgy Section B Metallurgy ◽

10.2298/jmmb190304043o ◽

2019 ◽

Vol 55 (3) ◽

pp. 315-324

Author(s):

M. Ozer

Keyword(s):

Iron Concentration ◽

Copper Recovery ◽

Atmospheric Conditions ◽

Iron Extraction ◽

Flotation Tailings ◽

Valuable Metals ◽

Sulfation Roasting ◽

Long Time ◽

Direct Leaching

The ancient flotation tailings from Lefke, Cyprus, have a potential for non-ferrous metals such as cobalt and copper from more than 9.5 million tons of reserves containing 0.38% Cu, 0.032% Co, and 22.6% Fe. Recovery of cobalt and copper from these tailings can provide great benefits from economic and environmental perspectives. While the ancient tailings were kept long time in storage in dumps, the characteristics of the material has become different from the common Co and Cu bearing ores. In order to extract these valuable metals, a process involving combination of roasting and leaching was applied in this study. Since this process responded to recovery to some extent, an innovative technique of using Na2SO4 as a promoter during roasting was proposed. Utilizing of Na2SO4 did not provide only higher metal extractions, but also resulted in high selectivity. In the scope of the study, following the determination of the mineralogy and chemical composition of the tailings, certain processes such as direct leaching and sulfation roasting with/without additives before leaching were applied. Since low metal extractions were obtained from direct leaching, a selective sulfation process was applied on the tailings before leaching in order to produce a pregnant solution containing higher amounts of Co and Cu metals by reducing the iron concentration. When sulfation roasting was performed without any additive, the desired selectivity could not be provided, since the sample was considerably oxidized under the atmospheric conditions in the past. Therefore, the usage of Na2SO4 as an additive with the amount of 25% at a roasting temperature of 700?C was tested. Consequently, Na2SO4 improved the sulfation and resulted in higher cobalt (90.1%) and copper (71.2%) recovery during leaching. Beside this, an improvement with a selective sulfation was obtained by combined effect of Na2SO4 addition and temperature, and the iron extraction decreased from 26.1% to 3.9%.

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Selective Acid Leaching of Copper and Zinc from Old Flotation Tailings

Materials Science Forum ◽

10.4028/www.scientific.net/msf.989.554 ◽

2020 ◽

Vol 989 ◽

pp. 554-558

Author(s):

Aleksandr Bulaev ◽

Vitaliy Melamud

Keyword(s):

Sulfuric Acid ◽

Acid Leaching ◽

Distilled Water ◽

Acid Solutions ◽

Iron Ions ◽

Flotation Tailings ◽

Ferrous Metals ◽

Non Ferrous Metals ◽

Sulfuric Acid Solutions ◽

Cu And Zn

The goal of the present work was to develop hydrometallurgical method based on acid leaching, which makes it possible to perform selective extraction of non-ferrous metals from old flotation tailings. Leaching was performed with sulfuric acid solutions (from 0.5 to 10%) and distilled water. Leaching was carried out using percolators and bottle agitator. Percolators were loaded with 100 g of old tailings, and leaching was performed with 100 mL of acid solutions. Pulp density during agitation leaching (S: L) was 1: 5. Two samples of old flotation samples were studied. The first sample of flotation tailings contained 0.26% of copper, 0.22% of zinc, and 17.4% of iron; while the second sample contained 0.36% of copper, 0.23% of zinc, and 23.2% of iron. Percolation leaching made it possible to extract up to 43 and 47% of Cu and Zn from the first sample. Extraction rate was maximum during the leaching with 1 and 2.5% sulfuric acid solutions. During the agitation leaching, the maximum extraction rate was reached with a 2.5% sulfuric acid solution (52 and 54% Cu and Zn), but the leaching rate with all solutions and distilled water differed insignificantly. Percolation leaching made it possible to extract up to 54 and 37% of Cu and Zn from the second sample of tailings, while agitation leaching made it possible to extract up to 34 and 68% Cu and Zn, respectively. The rate of non-ferrous metals extraction from the second sample with water did not differ significantly from that of obtained in the experiments with sulfuric acid solutions. In all experiments, the increase in the H2SO4 concentration led to the increase in concentrations of iron ions in productive solutions, which impedes the extraction of non-ferrous metals from solutions. Thus, it was possible to reach selective leaching of non-ferrous metals and to obtain solutions with relatively low concentrations of iron ions.

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Leaching of Ni and Cu from Mine Wastes (Tailings and Slags) Using Acid Solutions and A. Ferrooxidans

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.71-73.425 ◽

2009 ◽

Vol 71-73 ◽

pp. 425-428 ◽

Cited By ~ 4

Author(s):

Alexa Muñoz ◽

Denise Bevilaqua ◽

Oswaldo Garcia Jr.

Keyword(s):

Redox Potential ◽

Ferric Iron ◽

Iron Concentration ◽

Acid Leaching ◽

Bacterial Activity ◽

Mine Wastes ◽

Bacterial Leaching ◽

Flotation Tailings ◽

Acid Consumption ◽

Leaching Solution

The objective of this work is to evaluate the acidic and biological leaching of tailings containing Ni/Cu from a flotation and smelting plant. Acidithiobacillus ferrooxidans, strain LR, was used for bioleaching at pH 1.8 and chemical controls were run parallel to that. The acidic leaching was done within 48 hours at pH 0.5 and 1.0. In the slag inoculated flasks the redox potential was high (600 mV), thus indicating oxidative bacterial activity, however, the obtained results after 15 days showed only around 13% Ni and 8% Cu extractions, which were not different to those of the controls. For the flotation tailings bioleaching extractions were approximately 45% for Ni and 16% for Cu while differing figures were obtained for the chemical controls. These were 30% and 12% respectively. Here we could observe that the presence of bacterial activity led to a higher solubility of Ni. Acid leaching of slag showed higher nickel and copper extractions: 56% and 24% respectively at pH 0.5 and 21% and 11% at pH 1.0. However, the acid consumption was 320 and 150 Kg/ton of slag, respectively, both much higher than in bacterial assays. These results indicated that Ni and Cu solubilization from the slag is acid dependent no matter the redox potential or ferric iron concentration of the leaching solution. For flotation tailings, acid treatment showed extractions of 23% for Ni and 16% for copper at pH 0.5 and 22% and 28%, respectively at pH 1.0. The acid consumption was also higher: 220 and 120 Kg/ton, at pH 0.5 and 1.0, respectively. Based on own findings we could observe that acid leaching is found to be more effective for slag, though the acid consumption is much higher, while for the flotation tailings, bacterial leaching seems to be the best alternative.

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