Recovery of Indium from scrap LCD monitors

Abstract

The disposal of large quantities of electronic scraps generated world wide is causing not only environmental problem but also loss of resources. As a result this has produced an ever-increasing electronic waste stream, which has generated concerns regarding the E-waste's potential for adversely impacting the environment. Recovery of indium from scrap LCD monitors, which contain Indium metal, is becoming economically and environmentally justified. Natural resources are limited to meet the present demand of Indium metal so we have to recycle metals from secondary resources such as e-waste such as scrap LCD panels. Scrap crushed LCD panels were leached using different acids while optimizing various parameters viz. acid, temperature, contact time 79% dissolution of Indium was obtained using 2M hydrochloric acid at 60oC in 30 min. Ion Exchange process was used for recovery of In using INDION BSR resin from 100ppm Indium solution. Adsorption of In increases from 87.75% to 100% on increasing pH from 0.5 to 1.0 of the solution and almost 99.9% Indium was eluted using 0.2M H2SO4 in five contact stages. Pure Indium can be recovered in the form of salt by using evaporation or electrowinning process.