Recycling indium from waste liquid crystal display panel by vacuum carbon-reduction

This study investigated the recovery of indium from waste liquid crystal display (LCD) panel using vacuum carbon-reduction. First of all, high purity In2O3 was investigated. The results indicated that indium can be reclaimed from In2O3 using vacuum carbon-reduction in thermodynamics and dynamics. The conditions of 1223 K, 50 wt% carbon addition, 30 min, and 1 Pa were confirmed as the optimal conditions for pure In2O3 and high purity indium could be selectively recovered on condensing zone. Based on this, the experiment of the recovery of indium from waste LCD power was performed. The best parameters were confirmed as 1223 K and 1 Pa with 30 wt% carbon addition for 30 min. The recovery rate of indium from LCD powder could reach to 90 wt%. No hazardous materials produced in this process. Therefore, this technique provides the possibility of reutilization of LCD in an environmentally friendly way.