Comment on the feasibility of extracting copper from its ore chalcocite (Cu2S) by heating. Cu2S(s)- 2Cu(s) +S(s) It is favored at low temperature. It is favored at high temperatures. It is never favored as written. 0 O 0 …
Upper images emphasis on transforming changes started with darken rim of sulfide grains as earthy dark gray halo which in progress of reaction turn to metallic luster, obviously shown in c-f ...
Conclusion. The study assessed the effect of aeration on chalcocite heap leaching by analyzing the monitoring data from two chalcocite heap leach pads located in Chile, one with aeration and the other without aeration. The data showed that the copper leaching kinetics of the aerated heap was greater than that of the unaerated heap, but …
The dissolution process of chalcocite has been divided into two stages with CuS as an intermediate. 22,23,24 However, the first stage of chalcocite leaching is more complicated. There is a series of copper-deficient intermediates during the conversion of Cu 2 S to CuS, 25,26 in which Cu 1.8 S plays an important role. The dissolution process …
This chapter describes the important copper ore chalcopyrite (abbrv. ccp), as seen with optical, reflected light microscopy. Compositional data, main properties and optical parameters are first summarized (introductory table and preliminary remarks). The microscopic description of the ore is then presented, following a systematic scheme.
The amount of copper extracted from the chalcopyrite concentrate leached with seawater, 0.5 M of H2SO4 and 0.5 M of NaNO3 increased from 78% at room temperature to 91% at 45 °C in 96 h and 46 h ...
Malachite is the most common copper oxide mineral with the largest reserves. It is often associated with copper-bearing minerals, such as chalcocite and azurite. The chemical formula of malachite is Cu 2 (OH) 2 CO 3, and its theoretical copper mass fraction is …
There are two steps in the extraction of copper metal from chalcocite, a copper ore. In the first step, copper(I) sulfide and oxygen react to form copper(1) oxide and sulfur dioxide: 2 Cu 2 S ( s) + 3 O 2 (g) → 2 Cu 2 O (5) + 2 SO 2 (g) In the second step, copper( 1 ) oxide and carbon react to form copper and carbon monoxide: Cu 2 O (s) + C ...
To evaluate the feasibility of extracting copper from its ore chalcocite by heating, consider the changes in Gibbs free energy at different temperatures. Comment on the feasibility of extracting copper from its ore chalcocite (Cu2S) by heating. Cu2S (s)2Cu (s) +S (s) It is favored at low temperature It is favored at high temperatures.
Ore 2 had an approximate four-fold higher pyrite content than Ore 1, which would likely have aided in microwave-induced fracture of the ore and inter-granular breakage around associated copper ...
Grain of bornite (Bo; purple) and chalcocite (Cc; grey) showing an intergrowth that may have formed by chalcocite replacement of bornite, or may have formed by exsolution. The smooth boundaries of the bornite grains against the chalcocite suggest the latter. The margin of the bornite-chalcocite grains has been slightly replaced by hematite.
The typical Burra Burra ore contained 2% copper, 28% iron, 25% sulfur, and 1.5% zinc. The total production from the Burra Burra Mine was15 million tons of ore. Mining methods evolved over the years of production. This museum diagram shows a typical 1960s era mining stope using sub-level, longhole stoping. Blast holes are drilled from sub …
Chalcocite is the most abundant copper sulfide mineral after chalcopyrite [5,12], and it is the copper sulfide the most easily treated by hydrometallurgical routes [13].
Chalcocite is the most abundant secondary copper sulfide globally, with the highest copper content, and is easily treated by conventional hydrometallurgical processes, making it a very profitable mineral for extraction. Among the various leaching processes to treat chalcocite, chloride media show better results and have a greater industrial boom. …
Each grain-grade ore was mixed with resins and made into a thin section (4 pieces) to study. ... Influence of NH 4 HF 2 activation on leaching of low-grade complex copper ore in NH 3-NH 4 Cl ...
A 95% degree of liberation with d80 > 80 µm was obtained for chalcopyrite as the main copper mineral in the ore sample. The recovery rate and the grade in the concentrates were enhanced with ...
The silver-copper ore has been interpreted (Shockey and Renfro, 1974) to occur as solu- tion or roll-front deposits. ... Larger chalcocite grains, which are nearly spherical and have irregular margins, typically are 120-200/tm across. Limited mi- croprobe analyses give an average composi- tion of CuL86S for the copper sulfide grains. Near …
n at 25°C. Afte. that, the sample was centrifuged for 10 min at a rate of 9000 rpm/min.Flotation tests. Flotation tests for sulfide copper ore were conducted by using a laboratory FML-1 (237 AK) flotation machine with cell (volume of 0.5 L). 100 grams of a copper ore were firstly mixed with 0.5 L. distillate water in the flotation cell for 1 ...
Primary ore minerals in porphyry copper deposits, found in irregular grains within quartz veins and wallrock veinlets, display varying zonal distributions. Bornite-rich zones are common in orebody centers but absent in some deposits. Mineralization typically spans bornite-chalcopyrite, chalcopyrite-bornite-pyrite, and chalcopyrite-pyrite …
Grains of the chalcocite-like phase are found 6 m below the surface; and grains of chalcopyrite (CuFeS 2), ... 1976, Microscopy of copper ore at the Creta Mine, Southwestern Oklahoma, in Johnson, K. …
Secondary Cu-sulfides such as bornite, chalcocite, and covellite are important as they occur in a variety of ore deposit types e.g. iron oxide–copper–gold (IOCG) deposits of Olympic Dam, Prominent Hill, South Australia, Jalal-Abad deposit, Iran (Skirrow et al., 2002, Skirrow and Davidson, 2007, Cook et al., 2011, Pirajno et al., 2012 ...
mixed copper ore of Malanjkhand usin g microscopy, FTIR, XRD, XRF and FESEM. techniques. The results indicate that ore is of low grade with the predominant amount of. quartz with subordinate ...
Sandstone uranium, unconformity uranium, basalt copper, iron oxide copper gold deposits, and Kipushi Cu-Pb-Zn deposits can occur in the same districts. DEPOSIT DESCRIPTION Mineralogy All deposits contain one or more of the following minerals deposited in zones in this order: chalcocite and other C U 2 S minerals, bornite, chalcopyrite, pyrite, and
Chalcocite is one of the most industrially valuable copper-bearing minerals available for bioleaching. However, the efficiency of chalcocite bioleaching remains unsatisfactory. To better understand the bioleaching process of chalcocite, researches on chemical−biological dissolution mechanisms and leaching kinetics are reviewed.
Chalcocite. Chalcocite. Once of the most important copper-ore minerals, chalcocite occurs as a secondary mineral in or near the oxidized zone of copper sulfide deposits. Under surface conditions, the primary copper sulfides are oxidized, the soluble sulfates formed move downward reacting to form chalcocite, and thus, enriching the ore in …
Textures, Structures, and Grain Size 187. are replaced by chalcocite, digenite, covellite, and other Cu-rich sulfides. Acanthite may form in the supergene zone as silver is released from tetrahedrite. As oxidizing conditions extend to greater depths, covellite and digenite are ultimately replaced by chalcocite (Boyle, 2003).
Locally, ore minerals replace detrital grains. The sandstone ore is dominated by chalcocite, which is accompanied by digenite and covellite, whereas the Cu-Fe-S sulfides are not present. The most …
There are two steps in the extraction of copper metal from chalcocite, a copper ore. In the first step, copper(I) sulfide and oxygen react to form copper(t) oxide and sulfur dioxide: 2 Cu 2S(s) + 3 O2(g)--2 Cu 20(s)+ 2 SO2(g) In the second step, copper(I) oxide and carbon react to form copper and carbon monoxide: Cu20(s)+ C(s)-+2Cu(s)+ CO(9) Write the …
Sphalerite grains show relatively high copper contents ranging from 0.95 wt% to 2.9 wt%, whereas copper ore minerals have low or no zinc contents. And chalcocite grain shows 16 ppm gold concentration with low concentration of other elements such as Zn, Fe, As and Mo.
Grains of the chalcocite-like phase are found 6 m below the surface; and grains of chalcopyrite (CuFeS 2), ... 1976, Microscopy of copper ore at the Creta Mine, Southwestern Oklahoma, in Johnson, K. S., and Croy, R. L., eds., Stratiform copper deposits of the Midcontinent region, a symposium: Oklahoma Geological Survey Circular …
The low-grade copper ore leaching was enhanced by the silver under mesophilic conditions. ... Covellite and find-grain chalcocite are commonly found associated with pyrite and liberated large grains are the most common form of enargite. In the bioleach residue, leached chalcocite or covellite voids were readily observed and …
Chalcocite is formed either as a primary vein mineral or, more typically, in supergene deposits where it forms as a result of the redeposition of copper from the breakdown of minerals such as chalcopyrite or bornite. Chalcocite is distinguished with difficulty from digenite (Cu9S5) and djurleite (Cu31S16), both of which may form by the leaching of …
The main ore-mineral was found to be chalcocite, occurring together with lesser amounts of digenite, bornite, chalcopyrite, covellite, pyrite, cuprite, native copper, malachite, azurite, chrysocolla, ... through chalcocite, to native copper. The grain-size characteristics of the Witvlei ores were investigated, and cumulative frequency ...
CHALCOCITE – Cu2S. Chalcocite is a relatively common sulfide, being one of the most profitable Cu ores, with almost 80% by weight Cu. Crystals are very rare and obtain high prices in the market of collectible minerals. The planetary abundance of copper and sulfur, its wide distribution in the most varied geological environments and the high ...
Conclusion. A new process for recovering copper from chalcocite concentrate includes roasting in air (to about 0.5 percent S) followed by gaseous reduction to metal. These operations, conducted in two states of fluid-bed processing, were successful only when preceded by pelletizing.
