+32 (0) 16 32 12 13
Select Page

Ionic liquid process for recovery of yttrium and europium from fluorescent lamp phosphor waste

A breakthrough process has been developed to selectively recover the most valuable components of waste fluorescent lamp phosphor powder. By means of a functionalised ionic liquid, the red phosphor Y2O3:Eu3+(YOX) can be selectively dissolved without affecting the other components in the waste fraction. Of particular interest is the possibility to dissolve Y2O3:Eu3+ (YOX) without bringing the halophosphate phosphor in solution. The YOX phosphor is rich in the critical elements yttrium and europium and represents more than 70% of the intrinsic value of the lamp phosphor waste. After dissolution, europium and yttrium can be recovered from the ionic liquid phase by precipitation of a mixed yttrium-europium oxalate. At the same time, the ionic liquid is regenerated. By calcination, the oxalate can be transformed into Y2O3:Eu3+ with the same luminescence properties as a new batch of the lamp phosphor. Oxalic acid is the only chemical that is consumed in this cyclic process.


  • Rare-earth recycling using a functionalized ionic liquid for the selective dissolution and revalorization of Y2O3:Eu3+ from lamp phosphor waste
    Dupont and K. Binnemans
    Green Chemistry 17, 856–868 (2015).
    DOI: 10.1039/C4GC02107J
  • Process for recovery of yttrium and europium from lamp phosphor waste
    Binnemans and D. Dupont
    Patent application WO 2016065433 A1 (see link here)


SOLVOMET ISC is KU Leuven’s Industrial Service Centre for Circular Hydrometallurgy. We support mining, metallurgical & recycling companies in the development of more sustainable (circular, low-energy input) hydrometallurgical processes, using state-of-the-art lab & mini-pilot scale experimental facilities.

Corporate Presentation