Copper Oxide Minerals Research Articles

Detection of oxidized copper minerals and iron oxide minerals using high resolution satellite data

Detection of oxidized copper minerals and iron oxide minerals using high resolution satellite data

Influence of seawater and discard brine on the dissolution of copper ore and copper concentrate

It is well known that the Chilean mining industry is facing a shortage of water resources for the sustainable operation not only of existing plants but also of future projects. In addition, the depletion of oxide ores and those containing secondary sulfide copper will leave chalcopyrite ores as the main source of copper for future plants. To assure a sustainable hydrometallurgy plant, alternative water resources such as seawater and discard brine from desalination plants should be used together with a leaching process that can enhance the dissolution of chalcopyrite. This paper reports a study on the dissolution kinetics of finely ground copper oxide ore, chalcopyrite ore, and chalcopyrite concentrate leached in shake flasks, agitated reactors and columns using seawater and discard brine as the leaching solution. The type of chloride solution did not affect the dissolution of the copper oxide mineral. Regardless of the chloride solution used in the leaching test stirred at room temperature, the chalcopyrite dissolution did not exceed 4%, but increased to 90% when the temperature was increased to 50 °C. Column leaching of chalcopyrite ore with a P80 of 5 mm achieved a maximum dissolution of 43% of copper using discard brine at ambient temperature. The results show that curing time of the packed bed before the commencement of column irrigation and intermittent irrigation during leaching appeared to be important parameters to enhance dissolution of copper. Less irrigation time and more resting time can be beneficial for an industrial-scale heap leach plant.

Towards industrial implementation of glycine-based leach and adsorption technologies for gold-copper ores

ABSTRACTThe technology to selectively leach gold, silver and base metals from ores, concentrates, and wastes, using an alkaline glycine solution, has initiated significant interest in using the new technology in various environments such as in situ, in-place, dump, heap, and vat and agitated tank leaching. It has been shown that glycine acts synergistically with a number of other lixiviants to lower the net consumption of the other lixiviants while allowing low-cost glycine solution recovery. Glycine is a non-toxic, stable, environmentally benign reagent that is available in bulk industrial quantities. It has the ability to dissolve most copper oxide and sulphide minerals, as well as native copper, whilst not interacting with acid-consuming gangue nor dissolving iron and various or ubiquitous gangue elements. It acts synergistically with small amounts of cyanide to leach gold-copper ores at leach rates higher than either glycine or cyanide on their own, while significantly reducing cyanide consumption and eliminating detoxification requirements. The leaching behaviour of various glycine-based systems will be reviewed, followed by the evaluation of the adsorption of gold onto activated carbon. Where the economics merit it, copper can be easily recovered using solvent extraction or sulphide precipitation.

Bioleaching of Supergene Porphyry Copper Ores from Sungai Mak Gorontalo of Indonesia by an Iron- and Sulfur-Oxidizing Mixotrophic Bacterium

Environmentally friendly mining technologies have to be developed extensively to avoid the impact of mining activities with respect to environmental concern. One example of such technology is bioleaching which has been developed worldwide and is regarded as an appropriate technology for the extraction of metals from polymetallic ores such as supergene porphyry copper ores, mainly consisting of secondary copper sulfides, including chalcocite (Cu2S), covellite (CuS), or oxide minerals, i.e., cuprite (Cu2O) and tenorite (CuO). The extraction process for this complex ore generally requires high temperature, high pressure and/or high acid concentration. For the economic extraction of valuable copper from such ores, the bioleaching of supergene porphyry copper ore from Sungai Max in Southeast Sulawesi of Indonesia was investigated in shake-flask experiments at room temperature (28 °C) for 14 days using an iron- and sulfur-oxidizing bacterium (Alicyclobacillus sp.) indigenous to an Indonesian mine site. The main mineralogical composition of gangue minerals contained in this ore sample included quartz, muscovite, kaolinite and alunite. The relatively high copper extraction efficiencies were obtained over a 14-day period of the bioleaching experiments as a function of pH, pulp density and NaCl concentration. Therefore, the findings of this study provide the first information of bioleaching process of supergene porphyry copper ores in Indonesia that may highly be useful for developing an economical and environmentally friendly extraction process of such complex ores.

Biolixiviación de mineral cuarzo por <em>Acidithiobacillus ferrooxidans</em> en reactor de columna por gravedad

La biolixiviación es el proceso mediante el cual se extrae cobre de minerales sulfuros de baja ley usando microorganismos. La lixiviación química se aplica preferentemente para extraer cobre de minerales oxidados o mixtos, pero no existe información de aplicación de microorganismos en esta operación. En tal sentido, en la presente investigación se trabajó con reactores en columna por gravedad para procesos de lixiviación química, con cultivos bacterianos de Acidithiobacillus ferrooxidans en medio 9K y mineral de cuarzo que contenía cuprita y pirita, con diferentes tamaños de partícula. Se encontró que después de 24 días de lixiviación química se recuperó el 86% de cobre cuando se incluyeron bacterias, mientras que sin ellas sólo se recuperó el 54%. La mayor recuperación de cobre en ambos procesos se obtuvo en el siguiente orden de acuerdo al tamaño de partícula: 9,5 mm > 12,5 mm > 19,05 mm. Así, la aplicación de células bacterianas a procesos lixiviación química con minerales oxidados de cobre que incluyen cuarzo y células de A. ferrooxidans, aumenta la recuperación de cobre cuanto menor sea el tamaño de partícula del mineral. Esta tecnología puede ser utilizada por empresas mineras que aún siguen realizando lixiviación química convencional y se puede incluir en la operación la adición de microorganismos para aumentar la recuperación de cobre de minerales sulfurados incluyendo cuarzo.

An evaluation of hydroxamate collectors for malachite flotation

Abstract Copper oxide minerals, such as malachite, do not often respond well to traditional copper sulphide collectors, and require alternative flotation schemes. Hydroxamic acid collectors have been suggested as a means to directly float malachite; however, there is limited information on the effect of reagent structure on the performance of these collectors. This paper investigated the effect of five alkyl hydroxamates and two aromatic hydroxamates on the flotation of a synthetic ore composed of pure, fully liberated, malachite and quartz. Zeta potential measurements were used to aid in understanding reagent adsorption onto the surface of the two minerals. The collectors were then evaluated using bench scale flotation results. While zeta potential measurements suggested that all the collectors investigated selectively adsorb onto the surface of malachite, only benzohydroxamic acid and C8 alkyl hydroxamates were effective collectors in the flotation of malachite. Benzohydroxamic acid was the most selective; however, significantly lower dosages of C8 alkyl hydroxamates were required to obtain similar malachite recoveries, with minimal increases in quartz recovery. Benzo- and octylhydroxamic acid were further examined for the flotation of fine (−38 μm) particles. For fine particle flotation experiments the effect of temperature was also investigated as a means to improve the flotation performance.

Geochemistry, petrology, and mineralization in volcanic rocks located in south Neyshabour, NE Iran

This paper presents the new geochemical isotopes Sr and Nd, and the mineralization data for the south Neyshabour volcanic rocks located in NE Iran. Based on the chemical classifications, the studied rocks are basaltic trachy andesite, trachy andesite, trachyte, and trachy dacite in composition. All the analyzed volcanic rocks display enrichment in light rare earth elements (LREE) relative to the heavy rare earth elements (HREE), have significant negative Ti and Nb anomalies, and have a positive U anomaly. The tectonic discrimination diagrams for the volcanic rocks in the studied area show a post-collisional arc environment. These characteristics are the specifications of the subduction-related volcanic rocks generated in a post-collisional setting. The initial 87Sr/86Sr ratios ranging from 0.70408 to 0.70593and the eNdi values between +3.34 and +5 for the four samples analyzed indicate that the studied rocks are derived from a lithospheric mantle source. Finally, it is concluded that these volcanic rocks should have formed in a post-collisional environment that followed the Neo-Tethys subduction. There are strong evidence for copper mineralization in these volcanic rocks. The main copper oxide minerals are malachite and atacamite. The copper sulfide minerals such as chalcocite, minor bornite, and covellit are also present. Chalcocite is the most abundant sulfide ore mineral present in this area. This mineralization is observed as open space filling and thin veinlets, and it is partially controlled by linear structures and fault zones. Based on the identified characteristics, this ore deposit is hydrothermal. Carbonate alteration is frequently seen in the area but argillic alteration is very low, and this issue displays a hydrothermal solution with an alkaline pH.

The role of pulp potential and the sulphidization technique in the recovery of sulphide and oxide copper minerals from a complex ore

The role of pulp potential and the sulphidization technique in the recovery of sulphide and oxide copper minerals from a complex ore

The recovery of oxide copper minerals from a complex copper ore by sulphidisation

Kansanshi copper mine is situated in the north western province of Zambia. As a result of the mineral variations, the processing plant treats three distinct ore types, viz. oxide, sulphide and mixed. The objective of this study was to investigate the floatability of a complex Kansanshi mixed copper ore with a special focus on the sulphidisation process. Controlled potential sulphidisation (CPS) is preferred over slug sulphidisation as the industry standard for the flotation of oxide copper minerals. Two potential ranges were investigated in this study; −300 to −400mV and −400 to −500mV. Optimum flotation performance was observed in the potential range of −300 to −400mV and a NaHS:SIBX ratio of 7:1 during CPS. An economic analysis of the results showed that CPS did not change the recoveries compared to slug addition but required much lower dosages of NaHS.

An investigation into the leaching behaviour of copper oxide minerals in aqueous alkaline glycine solutions

Copper oxide minerals are normally extracted by acidic leaching followed by copper recovery with solvent extraction and electrowinning. However, copper oxide deposits often containing large amounts of acid consumable gangue leads to a very high acid consumption. In addition, if the oxide deposit also contains precious metals and iron bearing minerals, significant (lime) neutralisation costs are incurred to establish the conditions for subsequent cyanidation, with concomitant production of gypsum, potential formation of silver-locking jarosites and potential gel formation when acids interact with layer silicate minerals. In this study, an alternative aqueous alkaline glycine system has been employed to evaluate the batch leaching behaviour of copper oxide mineral specimens of the minerals azurite, chrysocolla, cuprite and malachite. The effects of glycine concentration and pH were investigated at ambient temperature and atmospheric pressure. Glycine concentration and pH both had a major effect on the copper extraction. Complete extraction of copper from azurite was achieved in <6h when glycine to copper ratio was 8:1. However, further investigation established the optimum leaching conditions as being pH11 and glycine to copper ratio of 4:1. Under such conditions 95.0%, 91.0%, 83. 8% and 17.4% of copper was extracted after 24h from the azurite, malachite, cuprite, and chrysocolla mineral specimens respectively. While the dissolution rates of the copper oxide minerals are markedly slower than acid leaching, the selective dissolution of copper over acid-consuming gangue minerals shows much potential. It was shown through UV–Vis spectroscopy that dissolved copper is in the cupric state and forms a neutral copper-glycinate complex under alkaline conditions. The study has shown that copper extraction from malachite, azurite and cuprite in aqueous alkaline glycine solutions is fast, whereas Cu extraction from chrysocolla was found to be poor and slow.

A DFT study on the structure–reactivity relationship of aliphatic oxime derivatives as copper chelating agents and malachite flotation collectors

Abstract Aliphatic oxime derivatives C 7 H 15 CX NOH (X = H, CH 3 , NH 2 or OH) have been commercially used as copper(II) extractants or flotation collectors, but the true nature of their reactivity toward Cu 2+ or mineral surfaces still remains elusive. Using density functional theory (DFT) method, the structure–reactivity relationship of these aliphatic oxime derivatives was evaluated at B3LYP/6-311 + G(d, p) level. The results indicated that the O or N atoms in the head group of octanaldoxime (OTAO), methyl n -heptyl ketoxime (MHKO), N -hydroxyoctanimidamide(HOIM) and n -octanohydroxamic acid (OTHA) are the chemical reaction center. The reactivity of the aliphatic oxime ionic species increases successively with the replacement of hydrogen atom by methyl, amino and hydroxyl, suggesting that the affinity of them to copper species is as follows: OTHA > HOIM > OTAO > MHKO, which coincides with the order of their binding energy toward Cu 2+ . The flotation performance of aliphatic oxime derivatives to malachite was in the order of OTHA > OTAO > HOIM > MHKO, which was in line with the combination effect of their reactivity and hydrophobicity. The established structure–reactivity relationship provides an atomic level understanding of the structural requirements for aliphatic oximes to recover cupric ions or copper oxide minerals.

Leaching of low-grade copper ores: A case study for 'Kraku Bugaresku-Cementacija' deposits (Eastern Serbia)

This paper deals with the investigation of column leaching of low-grade ores from the copper mine Cerovo, Serbia (the approximate Cu content in the ore ranges from 0.2 - 0.3 % with >10 % copper in the form of oxide minerals). The leaching experiments were performed using sulphuric acid solutions, whereby the kinetics of copper leaching was investigated with respect to acid concentration and solid to liquid ratio. The copper concentration in the leach solution ranged from 0.80 to 1.75 g dm-3. The total Cu recovery rate ranged from 30 to 56 %, whereas the recovery rate of copper oxide minerals ranged from 67 to 100 %. Furthermore, with increasing the amount of liquid phase, copper recovery increases as well, and copper oxide minerals were completely leached out. Besides copper ions, considerably high ferrous/ferric ion concentrations were achieved in the leach solution. This concentration was sufficiently high for the use of either solvent extraction or ion exchange techniques or both for further treatment of the leach solution.

مطالعات کانی سازی، ژئوشیمی، سیالات درگیر و ایزوتوپ پایدار گوگرد کانسار Cu-Zn-As باقرق با سنگ میزبان کربناته (شمال شرق انارک)

کانسار Cu-Zn-As باقرق در شمال شرق شهر انارک و در استان اصفهان قرار دارد. کانی‌سازی به‌صورت دیرزاد، ماهیت چینه‌کران و بافت و ساخت پرکننده فضای خالی در سنگ میزبان کربناتی رخداده است. کانی‌شناسی بخش درون‌زاد شامل کالکوسیت، کالکوپیریت، پیریت، اسفالریت، گالن، انارژیت، باریت و کلسیت و کانیهای بخش برون‌زاد شامل مالاکیت، آزوریت، کوولیت، کریزوکولا، کالکوسیت، سروزیت، اسمیت‌زونیت، مس طبیعی، هماتیت، گوتیت و لیمونیت می‌باشد. سنگ میزبان کربناتی در اطراف زون‌های کانه‌دار متحمل دگرسانیهای دولومیتی‌شدن و کلسیتی‌شدن شده است. مس به‌عنوان عنصر اصلی ذخیره (با میانگین 28/20 درصد وزنی) و پس از آن عناصر روی (با میانگین تقریبی 1 درصد وزنی) و آرسنیک (با میانگین تقریبی 1 درصد وزنی) می‌باشند. مطالعات سیالات‌درگیر روی کانی باریت نشان می‌دهد سیال کانه‌دار سولفیدی دارای محدوده دمای همگن شدن بین 259 تا 354 درجه سانتی‌گراد و میزان شوری بین 8 تا 13 درصد وزنی معادل NaCl می‌باشد. سیال کانه‌دار در مراحل پایانی کانی‌سازی با آبهای جوی دچار اختلاط شده و فاز تأخیری غیر سولفیدی کلسیتی با محدوده دمای نسبتا پایین ‌(78 تا 112 درجه سانتی‌گراد) و درجه شوری پایین (بین 3 تا 6 درصد وزنی معادل NaCl) را تشکیل داده است. محدوده مقادیر 34Sδ کانی‌ باریت کانسار باقرق بین 13+ تا 14+ در هزار بوده در حالی‌که محاسبه مقدار 34Sδ مربوط به سیال کانه‌دار پس از تصحیح دمایی بین 7- تا 8- در هزار به‌دست آمد. منشأ گوگرد باقرق با توجه به شباهت ایزوتوپ باریت با سولفات‌های دریایی کرتاسه، احتمالا از لایه‌های تبخیری این دوره زمانی تأمین شده است. این سولفا‌ت‌ها توسط فرآیند‌های ترموشیمیایی به‌صورت بخشی به گوگرد احیایی با مقدار ایزوتوپی سبک‌تر (حدود 21 در هزار) تبدیل و جهت ته‌نشست سولفیدها مورد استفاده قرار گرفته است. کانسار باقرق با توجه به خصوصیاتی همچون سنگ میزبان کربناته، غیاب فعالیت آذرین، بافت پرکننده فضای خالی، دگرسانی دولومیتی،کانی‌شناسی، ژئوشیمی ماده‌معدنی (وجود As و Sb بالا و عدم حضور Bi)، داده‌های دماسنجی و مقادیر ایزوتوپ گوگرد، شباهت زیادی با کانسارهای مس با سنگ میزبان کربناته در افریقا و به‌ویژه نوع سومب (Tsumeb) در نامیبیا نشان می‌دهد. کانسار باقرق احتمالا مرتبط با سیالات دگرگونی آزاد شده در حین فازهای کوه‌زایی مرتبط با بسته‌شدن اقیانوس نئوتتیس می‌باشد.

Acid leaching of oxide-sulphide copper ore prior the flotation: A way for an increased metal recovery

Copper mine "Cerovo"- East Serbia as well as the other ore bodies in its vicinity contain a significant amount of oxide copper minerals in their uper layers (&gt;40%). Processing of such mixed ores by the existing concentration technologies leads to a substantial copper losses (&lt;60%). Reduction of "oxide copper", by acid leaching prior the flotation concentration, can increase the overall copper efficiency up to more than 70% in the single-stage leaching, achieving an efficiency in the flotation concentration stage higher than 75%. Based on the performed experimental results the flow sheet for processing of the mixed oxide-sulphide copper ore is proposed.

Flotation of Copper Oxide Minerals by Mixed Collectors

In this study, the effects of important factors on malachite exploited from Tibet are investigated. Dosages of activating agents, depressants and collectors are essential to the effective recovery of copper in the flotation. The mixed collector ratio of SIBX: Armac C was varied as 0:1, 1:1, 1:2, 1:3, and 1:4. This investigation showed that using Armac C in conjunction with traditional SIBX collectors can successfully simultaneously recover copper oxides by flotation. The rougher scavenger copper recovery was as high as 85.2%.

Process Mineralogy Study on a Sandstone Copper Ore

In this thesis the object of study is a low grade sandstone copper with complex composition. Through the process mineralogy research on a sandstone copper ore,the result showed that the primary sulfide copper minerals are tetrahedrite and chalcopyrite; secondary sulfide copper minerals are bornite, chalcocite and azurite; the main oxide copper mineral is malachite; the main gangue mineral is quartz. The grade of copper is 0.77% and the oxidation rate is 45.45% in the run of mine, it is an oxide copper ore with not thoroughly oxidation. There is a part of disseminated particle size of copper minerals is relatively fine. Mainly sulfide copper minerals are paragenesis with dolomite and pyrite; oxide copper minerals are often blended with limonite. So the key of obtaining the good flotation index is selecting reasonably grinding fineness and making the part of fine-grained disseminated copper full liberation.

Separation Test of Oxide Copper Ore in Yunnan

A task of a refractory oxide copper ore in Yunnan has been studied, the grade of copper is 2.76% in crude ore. This ore has high oxidation and deep combination, the oxidation ratio is 42.32% and the combination ratio is 33.01%, so it is difficult oxide copper. Because the sulfide copper in crude ore containing 21.27%, so by experimental research, we decided to adopt the process of floating copper sulfides, and then sulfide oxide copper. In the flotation of oxidized copper minerals, we take the process of desliming, the copper minerals have recycled efficiently, while making a small precious metal--silver has been associated enrichment. Through closed-circuit test, we obtained the final concentrate, which the grade of copper is 20.38%, the recovery of copper is 65.44% and the grade of silver is 80.15g/t.

Application of Chelating Collectors in the Flotation of Copper Minerals

The application of new chelating reagents on the flotation of copper minerals has been paid much attention in recent years. These collectors have successfully extracted the copper minerals from the low-grade refractory ores, and one of the most important collectors is the alkylhydroxamate-based chelating reagent which shows the excellent flotation performance to the copper oxide minerals. Furthermore, the mixture of various chelating reagents can recover the copper sulfides and oxides simultaneously from the complicated copper ores, which is attributed to the synergy among collectors. Thus we conclude that it is an important flotation method by using chelating collectors in conjunction with other traditional collectors, by which the synergy can break through the limitation of single reagent and enhance the flotation efficiency.

Flotation of Low-Grade DongChuan Copper Oxide Ores with Xanthate and Hydroxamate Collectors

A hydroxamate collector AM28 is used in conjunction with Potassium Amyl Xanthate (PAX) to allow the flotation of the low-grade copper oxide ores from DongChuan Mine. A series of batch laboratory scale flotation tests are conducted for oxide copper minerals to establish the flotation response and the suitability of the collectors. From the rougher flotation tests performed, the highest copper recovery obtained is 78.9% at a concentrate grade of 2.5% using AM28 dosage of 740g/t and PAX dosage of 20g/t. With one stage of cleaning, the obtained copper grade increases to 9.6% with the copper recovery at 64.9%.

Flotation Responce of the Refractory Yangla Copper Oxide Ores with Hydroxamate Collectors

To establish the flotation response and suitability of the collectors, series of bench-scale flotation tests are conducted for the refractory oxide copper ores obtained from Yangla Mine in Yunnan province. A simple xanthate (PAX) is used as the sulphide collector and a chelating reagent of hydroxamate AM28 as the oxide collector. It is found and confirmed by mineralogical examination that AM28 successfully recovered all the discrete copper oxide minerals from the Yangla ore. The flotation tests show that the overall copper recovery is affected due to the minerals copper associated with goethite which is not amenable to flotation. The average copper recovery from the rougher tests is 38.4% with a concentrate grade of 3.19%. The additional cleaning flotation can increase the Cu grade in concentrate further.