Indium recovery from discarded LCD panel glass by solvent extraction

摘要

Indium is one of the key components in an LCD. In this work a potential recycling method involving leaching and solvent extraction was studied. Leaching of crushed LCD glass was investigated using HCl, HNO_3, or. H_2SO_4. Results of leaching kinetics showed that nearly complete leaching of indium can be achieved using 1 M HCl and 1 M H_2SO_4 in less than 8 h. A screening test was performed for the extraction and separation of indium from HC1 or H_2SO_4 with DEHPA, TBP, and Cyanex 272 or Cyanex 923. More than 99% of indium from the aqueous feed can be recovered with a purity of 90%, by extracting metal ions from 1 M or 0.1 M H_2SO_4 to 0.1 M DEHPA diluted in kerosene, and back-extracting with 1 M HC1.