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Mineral Deposits
Published in Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough, Earth Materials, 2019
Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough
Seven hundred miles south of Bingham Canyon, the Freeport‑McMoRan Corporation mines a larger porphyry deposit near Morenci, Arizona. Figure 13.34 shows a satellite image of the mine. Copper minerals were first discovered there by an Army battalion in 1865, and mining began in 1872. Today, Morenci, with pits that total almost 130 square kilometers (50 square miles), is the largest copper producer in North America. The mine extends beneath and between several large mountains next to the Morenci town site. Chalcocite and chalcopyrite, both sulfide minerals, are the primary copper ore minerals, but chrysocolla (copper oxide/hydroxide) and malachite (copper carbonate) are found and mined from oxidized ore zones. Although copper minerals are by far the most important ore minerals at Morenci, the mine also produces lesser amounts of sphalerite (zinc ore), galena (lead ore), and molybdenite (molybdenum ore). Table 13.1 lists important uses for all these metals. In particular, zinc is used to coat steel, lead is mostly used in batteries, and molybdenum goes into specialty alloys.
Leaching with Acids
Published in C. K. Gupta, T. K. Mukherjee, Hydrometallurgy in Extraction Processes, 2019
As an illustration of a large-scale hydrobased process involving acid leaching of oxide ores of copper, it is of interest to provide a brief appraisal of the operations of Inspiration Consolidated Copper Company1 located in Arizona. The principal sulfide mineral in the ore is chalcocite, and the oxidized minerals are mainly chrysocolla, malachite, and azurite. Major treatment schemes placed in operation in 1927 involved vat and agitation leaching, followed by flotation in later years. The leach solutions were dispossessed of copper by direct electrowinning and/or cementation. As the years passed, the plant introduced a number of alterations and developments. In 1955, dump leaching2 was introduced, and the dissolved copper in the off-solution from such dumps was also recovered by cementation. By the mid-1970s, five cementation plants were in operation, producing 15,909 t/year of cement copper. However, increasing labor and iron costs started to affect the cementation process. It was becoming more and more expensive. The introduction of solvent extraction to recover copper from dump-leach operations was a major step taken in later years. It worthily bridged the gap between leaching and copper recovery processes. Solvent extraction was conclusively demonstrated as a process that was a far more economical path to follow.
Hofrat en Nahas Cu-Au-U deposit, Sudan: Fluid inclusion evidence for a magmatic origin
Published in Adam Piestrzyński, Mineral Deposits at the Beginning of the 21st Century, 2001
Mineralization at HEN is composed of quartz, sulphide and calcite veins occupying late brittle fractures. Ore bodies are structurally controlled along shear zones and strike mainly NE (Fig. 1). They are 50 to 675 m long and 20 to 40 m thick and are crosscut by late-stage NW-striking faults on a mine scale (Fig. 1). Ore minerals are mainly composed of chalcopyrite and pyrite, with minor molybdenite and traces of uraninite and native gold. In the oxidation zone, the main copper secondary minerals are malachite and chrysocolla, while the main uranium mineral is torbernite (Master 1999). The ore reserves of the HEN deposit are some 20 Mt at 5.9% Cu. Associated with the copper is Au (up to 9 g/t), as well as U, Mo, Co, Ag, Pb and Zn (Binda et al. 1993). There is a strong positive correlation of Cu with Au and U (Master 1999).
Copper recovery improvement in an industrial flotation circuit: A case study of Sarcheshmeh copper mine
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2019
Mehrshad Asghari, Fardis Nakhaei, Omid VandGhorbany
Copper oxide minerals are formed as a result of supergene processes that take place when copper sulfide minerals are exposed to the effects of weathering and encompass a series of defined assemblages that reflect a variable pH, oxidizing geochemical environment, known as the oxide zone, in which the source rock, host rock mineralogy, and iron-copper sulfide mineral abundance, among other factors, specified which oxide minerals are formed (Chavez 2000; Reich et al. 2009). The mixed ore is contact zones between sulfide and oxide ore and shows difficulty in liberation of chalcopyrite, chalcocite, and covellite. Oxide ore is dominated by cuprite, tenorite, chrysocolla, malachite, and azurite set in a matrix of quartz, iron oxides, and iron hydroxides. The major gangue minerals in the deposit are dolomite, calcite, quartz, pyrite, and pyrrhotite. Sulfide ore is dominated by coarsely grained pyrite with the chalcopyrite set in a matrix of quartz, hematite, magnetite, feldspar, and muscovite mica.
Towards industrial implementation of glycine-based leach and adsorption technologies for gold-copper ores
Published in Canadian Metallurgical Quarterly, 2018
J. J. Eksteen, E. A. Oraby, B. C. Tanda, P. J. Tauetsile, G. A. Bezuidenhout, T. Newton, F. Trask, I. Bryan
In addition it has been shown that copper minerals, such as oxides (cuprite), native copper and various sulphide (chalcocite, djurleite, bornite, covellite and chalcopyrite) can be effectively dissolved from a gold-copper gravity concentrate in the presence of alkaline glycine and an oxidant at room temperature [8]. Subsequently it was also shown that various copper oxides (cuprite, malachite, azurite and chrysocolla) can all be dissolved in alkaline glycine, although copper extraction from chrysocolla tends to be poor compared to the other oxide minerals [9]. Tanda et al. also showed that the copper (cupric) glycinate species can be effective measured in alkaline solutions using UV–visible spectrometry. Furthermore Eksteen et al. [10] have shown that glycine can be used to leach copper from chalcopyrite-bearing concentrates or ores under alkaline conditions. Chalcopyrite concentrate leaching, under atmospheric pressure is shown to be significantly enhanced using a combination of mildly elevated temperature (50–60°C), ultrafine grinding and/or alkaline preoxidation (also at atmospheric pressure). Eksteen et al. [10] then also introduce a few flowsheets involving chalcopyrite leaching, where copper recovery from solution is achieved by either solvent extraction or by sulphide precipitation as a pure, coarse-grained, covellite precipitate. Glycine is retained in the aqueous solution in all cases and can be recycled after metal recovery from solution, if economically worthwhile.
Selective Flotation of Copper Oxide Minerals with A Novel Amino-Triazole-Thione Surfactant: A Comparison to Hydroxamic Acid Collector
Published in Mineral Processing and Extractive Metallurgy Review, 2020
Jun Liu, Zhe Hu, Guangyi Liu, Yaoguo Huang, Zhiyong Zhang
The raw materials for bench-scale flotation tests were the mixed oxide-sulfide copper ores of Dongchuan copper mine (Yunnan, China). The copper-bearing minerals were chalcopyrite, bornite, chalcocite, covellite, tennantite, and some copper oxide minerals such as malachite, chrysocolla, and cuprite. The iron-bearing minerals included pyrite and hematite. The non-sulfide gangue minerals contained dolomite, calcite, quartz, muscovite, and feldspar. The oxidation proportion of copper minerals in the samples was about 30.26% and malachite was the dominated copper oxide minerals. The XRF results of the ore samples were also presented in Supporting Information (Table S1).