Recovery of indium from used indium–tin oxide (ITO) targets

Abstract A novel hydrometallurgical process was developed for the recovery of indium metal from used indium and tin oxide (ITO) targets, which includes acid leaching, removing tin from leach solution by sulphide precipitation and depositing sponge indium by zinc cementation. The leaching of indium reached 99% with ITO powder size of less than 75 um and initial acid concentration of 100 g/L H 2 SO 4 at L/S ratio of 8–12 and 90 °C for 2 h, while only about 8% of tin was leached out. Tin in the leach solution was reduced to 10 mg/L and the loss of indium was less than 1% by sulphide precipitation under H 2 S partial pressure of 101.3 KPa and 100 g/L H 2 SO 4 at 60 °C for 10 min. Pure sponge indium from purified In 2 (SO 4 ) 3 solution was obtained using zinc plate cementation at pH 1–1.5 and 65 °C.

[1]  H. Matsuda,et al.  Study on reaction kinetics and selective precipitation of Cu, Zn, Ni and Sn with H₂S in single-metal and multi-metal systems. , 2008, Chemosphere.

[2]  J. Tay,et al.  Effect of operating variables on rejection of indium using nanofiltration membranes , 2004 .

[3]  Hou Chen,et al.  Extraction and separation of In(III), Ga(III) and Zn(II) from sulfate solution using extraction resin , 2006 .

[4]  Alison Lewis,et al.  Review of metal sulphide precipitation , 2010 .

[5]  John Aurie Dean,et al.  Lange's Handbook of Chemistry , 1978 .

[6]  Sheng-Jen Hsieh,et al.  Process for recovery of indium from ITO scraps and metallurgic microstructures , 2009 .

[7]  K. Nakashima,et al.  Effect of tin oxide dispersion on nodule formation in ITO sputtering , 2002 .

[8]  Wei-Lung Chou,et al.  Electrochemical removal of indium ions from aqueous solution using iron electrodes. , 2009, Journal of hazardous materials.

[9]  R. V. Hille,et al.  An exploration into the sulphide precipitation method and its effect on metal sulphide removal , 2006 .

[10]  Hui-ming Liu,et al.  Recovery of indium from etching wastewater using supercritical carbon dioxide extraction. , 2009, Journal of hazardous materials.

[11]  A. Lewis,et al.  Factors Affecting Metal Removal in Mixed Sulfide Precipitation , 2006 .

[12]  A. Alfantazi,et al.  Processing of indium: a review , 2003 .

[13]  G. Cote,et al.  Study of the removal of Cd(II) from phosphoric acid solutions by precipitation of CdS with Na2S , 2002 .

[14]  Guido Grause,et al.  Recovery of indium from In2O3 and liquid crystal display powder via a chloride volatilization process using polyvinyl chloride , 2009 .