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Hydrometallurgy is a method for obtaining metals from their ores. It is a technique within the field of extractive metallurgy involving the use of aqueous chemistry for the recovery of metals from ores, concentrates, and recycled or residual materials.〔Brent Hiskey "Metallurgy, Survey" in Kirk-Othmer Encyclopedia of Chemical Technology, 2000, Wiley-VCH, Weinheim. 〕 〔F. Habashi "Recent Trends in Extractive Metallurgy" Journal of Mining and Metallurgy, Section B: Metallurgy 2009, Volume 45, pp. 1- 13. 〕 Metal chemical processing techniques that complement hydrometallurgy are pyrometallurgy, vapour metallurgy and molten salt electrometallurgy. Hydrometallurgy is typically divided into three general areas: *Leaching *Solution concentration and purification *Metal or metal compound recovery ==Leaching== Leaching involves the use of aqueous solutions to extract metal from metal bearing materials which is brought into contact with a material containing a valuable metal. The lixiviant solution conditions vary in terms of pH, oxidation-reduction potential, presence of chelating agents and temperature, to optimize the rate, extent and selectivity of dissolution of the desired metal component into the aqueous phase. Through the use of chelating agents, one can selectively extract certain metals. Such chelating agents are typically amines of schiff bases.〔Peter A. Tasker, Christine C. Tong, Arjan N. Westra "Co-extraction of cations and anions in base metal recovery" Coordination Chemistry Reviews 2007, vol. 251, pp. 1868–1877. 〕 The five basic leaching reactor configurations are in-situ, heap, vat, tank and autoclave. 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「hydrometallurgy」の詳細全文を読む スポンサード リンク
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