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List of Chemical Substances
Published in T.S.S. Dikshith, and Safety, 2016
Copper sulfate (anhydrous form) is green or gray-white powder, whereas pentahydrate, the most commonly encountered salt, is bright blue. The anhydrous form occurs as a rare mineral known as chalcocyanite. Hydrated copper sulfate occurs in nature as chalcanthite. Copper sulfate is made by the action of sulfuric acid with a variety of copper compounds. Copper sulfate is used in hair dyes, coloring glass, processing of leather, textiles, and in pyrotechnics as a green colorant.
Accelerating copper leaching from a complex ore containing atacamite: optimisation and kinetic studies
Published in Canadian Metallurgical Quarterly, 2023
Sepideh Javanshir, Hojat Imantalab, MohammadBagher Fathi
The copper processing varies depending on the nature of copper minerals [5]. Table 1 shows the solubility of different copper minerals based on the leachability index used for the amenability of different minerals to dissolve in acid, where 1 indicates complete leaching and 0 represents no dissolution. As can be seen, sulphide-rich ores have limited dissolution in acid with a poor leachability index, for example, up to approximately 20% of the chalcocite can leach, however, copper oxides have a high tendency for acid leaching. It is expected that 100% of the copper present in the following minerals: chrysocolla, malachite/azurite, brochantite, chalcanthite, atacamite, antlerite, tenorite, pseudomalachite, and neotosite can be dissolved in acidic media. Therefore, these criteria can predict the dissolution rate based on mineralogical properties. Hence, copper processing varies depending on the nature of copper minerals [6].
Afforestation may influence changes in tailing heaps in a long time
Published in International Journal of Phytoremediation, 2021
Rogelio Carrillo-González, Ma del Carmen A. González-Chávez
Because of the MR are usually deposited in a slurry, the tailings heaps are a sequence of layers. Huot et al. (2014) described that the Technosol profile is formed of a superimposition of layers of the ground rock. It is the result of meteoric diagenesis leading the formation of new minerals, such as gypsum derived from sulfide oxidation (Schad 2014; Lindsay et al. 2015). Chemical changes of calcite (Lehmann 2006), dolomite, sphalerite, pyrite, arsenopyrite, cerussite, melanterite, and chalcanthite lead to minerals in different degree of weathering (Mendez and Armienta 2003). The mine residues have been oxidized forming a yellow-red hardpan (Schad 2014), which looks like a petrocalcic horizon, due to the adhesive effect of carbonate and sulfate. Similar soil evolution has been reported for other industrial residues (Huot et al. 2014). Sulfide oxidation releases sulfate and thiosulfate ions (Lindsay et al. 2015), which may form new minerals (Mendez and Armienta 2003). This may be observed by changing the color from gray to yellow.
On the optimization of the crystallization related to an aqueous copper sulfate (CuSO4.5H2O)
Published in Mineral Processing and Extractive Metallurgy, 2021
Hadi Alimohammadizadeh, Ali Behrad-Vakylabad, Sattar Ghader
Thermochemical characterization of natural chalcanthite and synthetic hydrous copper sulfate (blue vitriol) by using the melt solution calorimetry in accordance with Hess's laws shows that the standard molar enthalpies of formation were −(2267.2 ± 4.1) kJ.mol−1 for natural chalcanthite and −(2272.6 ± 6.0) kJ.mol−1 for synthetic hydrous copper sulfate (blue vitriol) at ΔfH0m (T = 298.15 K) which can be used the quantitative modeling of the physicochemical conditions related to crystallization (Bissengaliyeva et al. 2016).