Resumen de Beneficiation and recovery of indium from liquid-crystal-display glass by hydrometallurgy
Basudev Swain, Chinmayee Mishra, Hyun Seon Hong, Sung Soo Cho
Considering indium scarcity, the end-of-life (EOL) LCD, which accounts for up to 90% of market share can be a feasible secondary resource upon successful recycling. In the preferred hydrometallurgical process of such critical metals, leaching is the essential primary and essential phase has been investigated. In this process, LCD was mechanically separated along with other parts from EOL TVs through a smartly engineered process developed at our institute, Institute for Advanced Engineering (IAE), the Republic of Korea. After removing plastics and metals from the LCD, it was mechanically shredded for size reduction. The mechanically shredded LCD waste was leached with HCl for recovery of indium. Possible leaching parameters such as; effect of acid concentration, pulp density, temperature and effect of oxidant H2O2 concentration were investigated to identify the best conditions for indium extraction. Indium (76.16 × 10−3 g/L) and tin (10.24 × 10−3 g/L) leaching was achieved at their optimum condition, i.e. lixiviant of 5 M HCl, a pulp density of 500 g/L, temperature 75 °C, agitation speed of 400 rpm and time for 120 min. At optimum condition the glass, plastic and the valuable metal indium have completely been separated. From indium enriched leach liquor, indium can be purified and recovered through hydrometallurgy.
