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Base Metals Waste Production and Utilization
Published in Sehliselo Ndlovu, Geoffrey S. Simate, Elias Matinde, Waste Production and Utilization in the Metal Extraction Industry, 2017
Sehliselo Ndlovu, Geoffrey S. Simate, Elias Matinde
Nickel is generally produced from sulphide minerals, and from laterite and saprolite ores (BGS, 2008; Crundwell et al., 2011; European Commission, 2014a). In general, the most common mode of occurrence of some of the important nickel-bearing minerals found in economic deposits include (BGS, 2008; Crundwell et al., 2011) (1) sulphide-hosted minerals such as pentlandite ((Fe,Ni)9S8), which is the most important nickel-bearing sulphide mineral in economic deposits, occurring together with pyrrhotite (Fe1−xSx), millerite (NiS), chalcopyrite (CuFeS2) and pyrite (FeS2) in mafic and ultramafic (iron and magnesium rich) igneous rocks; (2) laterites related to ultramafic rocks, and these include garnierite ((NiMg)3Si2O5(OH)4 and nickel-ferrous limonite ((Fe,Ni)O(OH)) (BGS, 2008); (3) hydrothermal replacement of pentlandite in mafic intrusions typically containing minerals such as niccolite (NiAs) and (4) hydrothermal veins hosting sulphide minerals such as siegenite ((Ni,Co)3S4). Although laterites constitute about 70% of the nickel contained in land-based deposits, their exploitation only contributes to about 40% of the world nickel production (BGS, 2008; Crundwell et al., 2011).
Applications
Published in Alan Jones, Brian McNicol, Temperature-Programmed Reduction for Solid Materials Characterization, 2014
TPR has also been used to study natural garnierite, a nickel� containing mineral [11,12]. The mineral consists of a mixture of a talclike phase and a fiberlike phase. The major amount of nickel is associated with the talclike phase. The TPR profile shows three maxima in the rate of hydrogen uptake, corresponding to three distinct nickel species. The first low-temperature maximum is associated with the talclike phase and corresponds to the reduction of a Ni-oxide-hydroxide phase physically adsorbed on the talclike particles. The broad intermediate maximum of weak intensity is found in a temperature region slightly higher than expected for the reduction of bulk nickel oxide (as determined by reoxidation and a subsequent TPR) and may be due to the reduction of minor quantities of Ni2+ present in the fiber phase. The third maximum is observed only when the mineral starts to decompose and may be assigned to the reduction of lattice-substituted Ni2+ ions, which are liberated only when the crystallinity of the material declines. This kind of Ni2+ is predominantly present in the talclike material.
Ore field structures of the Uralian supergene Nickel deposits
Published in Vladimir Litvinenko, Innovation-Based Development of the Mineral Resources Sector: Challenges and Prospects, 2018
N.I. Vorontsova, A.M. Duryagina, I.V. Talovina
Structural analysis of ore fields has never gained the focused attention of researchers investigating supergene nickel deposits of the Urals. Nevertheless, in the structural and genetic point, two main morphological types are distinguished among them: areal and fractural weathering crusts. Actually, today the genesis of these deposits suggests two points of view: supergene and hypogene. The first and predominant one was amplified by I. Ginzburg and his followers and nowadays by many other scientists who are studying laterite formations of the tropical belt of the Earth (Butt 2013, Freyssinet et al. 2005, Goldfarb et al. 2010, Marsh et al. 2011, Razumova 1977). It is based on the fact that almost all of supergene nickel deposits are located in the area of modern tropical climate of the Earth. The second one, hypogene point of view was expounded by A. Aleshkov, D. Ulyanov, V. Razumova (1977), N. Kheraskov, B. Mikhailov (1997, 2003), A. Vershinin, V. Nikitin, V. Maleev (Edelstein 1968, Samama 1986). Recent researches are based on the fact that many of these deposits, primarily fracture-type deposits, show a close connection with tectonic zones of different scale. This group of scientists is not against the formation of many types of nickel deposits in the supergene zone, but they are drawing attention to the participation of hydrothermal endogenous factor in this process in the form of thermal waters of deep origin. In accordance with this theory, rocks of supergene nickel deposits are seen as low-temperature near-vein or wallrock metasomatites similar to hydrothermal formations. At the same time, it is interesting to note that the hypothesis of hydrothermal formation of nickel ores of this type was firstly supposed by researchers of New Caledonia deposits using the example of garnierite veins. As an argument, they favored a wide surface of areal development of garnierite veins in comparison with the surface of weathered rocks. This allowed V. Razumova (1977) to propose a hydrothermal-vadose model of formation for a part of the fractural crusts: linear, karstic, and near-faulted, and later B. Mikhailov (1997) to propose a thermal-hypergenic model. Both genetic approaches are not of just only academic interest. World reserves of silicate nickel ores significantly exceed the reserves of sulfide ores, which are quite rapidly being depleted (Mudd 2010, Petrov et al. 2013). Standing out hydrothermal varieties among all silicate nickel ores is of great prognostic and exploratory significance, since the reserves of nickel ore in the Urals are considerably developed, and new ideas essentially expand the range
Advanced Review on Extraction of Nickel from Primary and Secondary Sources
Published in Mineral Processing and Extractive Metallurgy Review, 2019
Pratima Meshram, Banshi Dhar Pandey
Nickel is a transition metal exhibiting the properties of a mixture of ferrous and nonferrous metal. It is both siderophile (i.e., associates with iron) and chalcophile (i.e., associates with sulfur). As stated above bulk of the nickel mined comes from two types of ore deposits: magmatic sulfide deposits where the principal ore mineral is pentlandite [(Ni,Fe)9S8].laterites where the principal ore minerals are nickeliferous limonite [(Fe,Ni)O(OH)] and garnierite (a hydrous nickel silicate).