| Abstract |
Given the criticality of indium (In) in high-tech applications, spent LCD screens can represent a viable secondary In resource. In this work, an innovative and alternative technology to selectively leach In from spent LCD screens using a microbial chelating agent, desferrioxamine E (DFOE), was developed. Indium was concentrated from spent LCD screens by implementing an adapted pre-treatment procedure, allowing the isolation of an indium -rich glassy fraction. During leaching, the competition between aluminum (Al) and In for complexation with DFOE leads to the precipitation of In(OH) 3 at low DFOE concentrations (12 - 240 mu M). After adjusting the optimal conditions (fraction size: 0 - 36 mu M, pH: 5.5, S/L ratio: 1 g/L, 25 degrees C), the In leaching yield reached 32%, ten times higher than Al over 90 days with 5 mM DFOE. Thus, achieving high In recovery is possible through i) prolonging leaching durations, ii) selective leaching, and iii) minimizing Al interference. This is the first attempt to selectively leach In using a selected siderophore from end -of -life products with high concentrations of non -targeted elements (i.e. Al, Si, and Ca). This study demonstrates the potential of generating indium -rich leachates, which can be subsequently processed through the GaLIophore technology for In refining. |
