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Leaching with Ferric and Cupric Ions
Published in C. K. Gupta, T. K. Mukherjee, Hydrometallurgy in Extraction Processes, 2019
The mineral bornite (Cu5FeS4) is found frequently associated with chalcopyrite or chalcocite. However, it can also be an important copper mineral in its own right. A study of the ground bornite ore containing some chalcocite in ferric sulfate was conducted by Sullivan.16,56 The dissolution curve obtained by plotting copper extraction vs. time showed two distinct parts: a very rapid initial step followed by a slower secondary stage. Over the temperature range of 23 to 98°C, the initial step increased only moderately with increasing temperature for the sulfate medium. The dissolution rate was independent of the ferric sulfate concentration over the range 0.25 to 10% Fe3+. The pH of the solution did not alter the dissolution rate at constant temperature. Sullivan presented the overall leaching of bornite by the following equation: () Cu5FeS4+12Fe3+→5Cu2++13Fe2++4S0
Other Thermoelectric Materials
Published in Zhifeng Ren, Yucheng Lan, Qinyong Zhang, Advanced Thermoelectrics, 2017
Pengfei Qiu, Xun Shi, Lidong Chen, Jiehe Sui, Jing Li, Zihang Liu, Zhifeng Ren, Takao Mori, Jun Mao
Bornite (Cu5FeS4) is a widespread copper sulfide mineral that occurs in a variety of ore deposits formed under a wide range of geological conditions. Ultralow κL has been observed in this natural sulfide because of its inherent and unusually complex crystal structure. By forming a solid solution with Cu2S, the electronic transport and the TE performance of bornite are easily tuned to achieve a maximum ZT value of 1.2 at 900 K.22 High-temperature TE properties of diselenide (MCrSe2, M = Cu, Ag) materials have also been explored. These compounds are naturally layered materials. ZT values around 1–1.4 have been reported for CuCrSe2 and AgCrSe2 on account of their extremely low κL value.24,25 Cu7PSe6 has been reported with an extraordinary low thermal conductivity reaching below the glass limit. This may be associated with the soft phonon modes attributed by the molten copper sublattice. Eventually, the maximum ZT of 0.35 was achieved at 575 K.26 The monoclinic Cux+yBi5−Se8 structure contains multiple disorders such as randomly distributed substitutions and interstitial disorders of Cu as well as asymmetrical disorders of Se, which simultaneously leads to an extremely low κL.27
Soil Contaminations in Arid and Semiarid Land
Published in Saeid Eslamian, Faezeh Eslamian, Handbook of Drought and Water Scarcity, 2017
Saumitra Mukherjee, Kamana Yadav, Saeid Eslamian
An XRD analysis of soil samples was done to reveal the bulk mineralogical composition. Quartz/silica formed the predominant fraction in the bulk mineralogy of all the samples analyzed. This correlates with the samples being predominantly sandy in nature. Calcite was found in almost all the samples to be the next major mineral present though comparatively less dominant than quartz/silica. Traces of other minerals such as praseodymium oxide, bornite, and fluorite were also found to be present. Very trace amounts of alumina, hematite, and chromium were also found. Some background traces of uranium oxide were evident in almost all the samples though present only in very minute/trace quantities. The presence of trace amounts of uranium oxide and praseodymium oxide indicates the possibility of the presence of the mineral monazite. The presence of bornite (a common copper-bearing mineral sometimes used as an ore of copper) indicates the possibility of sulfide mineralization through igneous intrusions. The overall mineralogical composition of samples indicates their felsic origin.
Enhanced degradation of reactive black 5 via persulfate activation by natural bornite: influencing parameters, mechanism and degradation pathway
Published in Environmental Technology, 2023
Hongmin Zhang, Xudong Wang, Xiaochen Zhao, Yonghao Dong, Wanying Wang, Yongtao Lv, Shumiao Cao, Lei Wang
Natural mineral materials are abundant and have attracted increasing attention. As reported, persulfate activation with sulfide minerals such as chalcocite [27], brochantite [28] and pyrite [29] was used to degrade emerging pollutants. Natural bornite (Nbo, mainly Cu5FeS4) is a major mineral for copper refining and ranks third in world reserves [30]. Bornite is a bimetallic sulfide mineral with high catalytic reactivity, making it ideal for pollutant degradation and environmental remediation [31]. However, there are few reports on the use of bornite-activated PDS for RBk5 degradation. Furthermore, the activation mechanism of the Nbo/PDS process is unclear. Some reports have shown that a nonradical pathway is also involved in the mineral activation of PDS for pollutant removal in addition to the traditional free radical pathway [28, 32]. Thus, it is essential to deepen the understanding of the relationship between bornite and PDS.
Spectroscopic characterisation of feedstock for copper smelters by machine-learning
Published in Canadian Metallurgical Quarterly, 2023
Adam Bernicky, Boyd Davis, Jack Barnes, Hans-Peter Loock
The sensor system was used to record spectra of neat iron and copper metal powders and of a variety of reference minerals. These minerals were chalcopyrite CuFeS2, bornite Cu5FeS4, pyrite FeS2, pyrrhotite Fe(1-x)Sx (x = 0–0.2), and sphalerite (Zn, Fe)S. All are commonly present in copper smelting processes. For each mineral, 250 spectra were collected for a total of 1250 reference spectra. In addition, the mineral powders were then mixed with another mineral at 25 weight-% intervals to produce 30 unique binary mixtures. We recorded an additional 7500 spectra (30 × 250) for those binary mixtures, giving a total of 8750 spectra. Lastly, a set of 13 copper concentrate samples were obtained from an industrial partner; they include one revert sample. 500 spectra were collected from each sample for a total of 6500 ‘industrial’ spectra.
Alteration and mineral zonation at the Mt Lyell copper–gold deposit, Tasmania
Published in Australian Journal of Earth Sciences, 2018
The dominant copper mineralogy in the 12 West deposit is bornite with lesser amounts of chalcopyrite. Chalcocite–digenite [Cu2S], pyrite, tennantite and hematite (two textural phases) are other important phases. Other minor minerals identified were covellite [CuS], mawsonite [Cu6Fe2SnS8], hexastannite [Cu2FeSnS4], galena, magnetite and tentatively enargite [Cu3AsS4]. All these minerals, except magnetite, have been identified in previous studies. Minerals that have been previously recognised but not recognised in this study include: linnaeite [Co3S4], betechtinite [Pb2(Cu,Fe)21S15], hessite [Ag2Te], djurleite [Cu31S16], stromeyerite [AgCuS] and wittichenite [Cu3BiS3].