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ABSTRACT The by-products of zinc refineries are used as the primary mineral resources for the commercial production of indium. The discarded LCDs containing adequate amount of indium is rather worth as its secondary resources compared to the by-products of zinc refineries. Mining and recycling rates of indium, respectively from minerals and waste LCDs are in progress to meet its huge demand. Recycling of the LCDs has been dominating over mining, as presently 480t of indium are produced annually from mining, however, that of 650t annually from recycling. Different aspects of the extractive metallurgy of indium are summarized in this review paper. KEYWORDS: Indium, pyrometallurgy, hydrometallurgy, biometallurgy, recycling, recovery https://www.tandfonline.com/eprint/hF4dWP3eMjyeq7trE9zV/full
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... They are regarded as strategic metals because of their applications in automobiles, jewelry, agriculture, chemical, petroleum, electrical, electronics, medical and aerospace industries. They have essential uses in environmentally related technologies such as catalytic converters and fuel cells (Brenan 2008;Butterman 1988;Fernandez 2017;Kao and Garbers-Craig 2020;Kraemer, Junge and Bau 2017;Pradhan, Panda and Sukla 2018;Vermaak 1995;Xiao and Laplante 2004;Yakoumis et al. 2020). The concentration of platinum group ores in the earth's crust is very rare (̴ 10 −6 -10 −7 %) (Barkov and Zaccarini 2019;Nikoloski and Ang 2014). ...
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