Indium Recovery from Bearing Alloy via Pyrometallurgical Chlorination Process Utilizing Ammonium Chloride

摘要: The chlorination process utilizing ammonium chloride as reagent has been employed for the recovery of elements with emphasis on indium from bearing alloy through vaporization chlorides. It was found that took place by heating model sample in presence chloride. influence parameters, such reaction temperature and gas flow rate, investigated. addition activated carbon resulted adsorption surface. present result indicates possibility transport target element to pores carbon. (doi:10.2320/matertrans.M2013206) development valuable metals wastes is great importance view resource securities. Conventional processes are based technique hydrometallurgy, where dissolved e.g., acid enriched various types extracting reagent, which have developed past decades. As pyrometallurgical processes, metallurgy one attractive methods extraction elements, it enables spatial separation a single step according difference vapor pressure So far, series basic studies reported literature, 1­8) chlorine or hydrogen gases mostly used reagent. In practical application however, pay special attention handling corrosive gases. Ammonium an alternative utilized, instance, laboratory-scale synthesis rare earth 9) much easier than gaseous reagents, so utilization way. Recently, Itoh et al. demonstrated neodymium Nd­Fe­B magnet scrap could be selectively chlorinated. 10) our previous 11,12) we results pyrometallur- gical treatment wastes. can recovered dental metal recycling sludge well tin oxide, transparent conductor, deposited glass apparently described In2O3ðs Þþ 6NH4ClðsÞ ! 2InCl3ðg 6NH3ðg 3H2Oðg Þð 1Þ One advantages proposed chemicals considerably reduced when position known: directly put onto specimen exists, surface case ITO-deposited glass. contrary, entire should immersed bath conventional hydro- metallurgical may lead higher cost very small amount exists sample, form thin film. paper, address made lead, tin, plated substrate improvement tribological property. parameters studied discussed. 2. Experimental Procedure 2.1 Materials material treatment, samples were kindly supplied Daido Co., Ltd. A iron (20mm © 50mm 2mm) above copper, then nickel intermediate layer finally Pb­In­Sn (Pb:In:Sn = 8:1:1 mass%) plated. order avoid diffusion upper into inner copper layer. average contents Pb, Sn 21, 2.7 2.7mg, respectively. Given (99.5%, Wako pure chem. Ltd.) Typical composition NH4Cl, defined 100 � mNH4Cl=mSample, mNH4Cl mSample mass specimen, respectively, 6mass%. ensure sufficient contact between NH4Cl surface, ethanol poured dried.