Recovery of LaPO4:Ce,Tb from waste phosphors using high-gradient magnetic separation

LaPO4:Ce,Tb (LAP) containing high terbium concentration was successfully recovered from waste phosphor from end-of-life fluorescent lamps by high-gradient magnetic separation (HGMS). In addition to HGMS, some contaminants in the waste phosphor, e.g., iron oxide and glass powder, were also removed by sieving and sedimentation. Repeating the magnetic separation procedure three times yielded LAP with a purity of 87%. Luminescence spectra intensities of recovered LAP were as high as 95% compared with virgin LAP. This recovery method will be useful during rare-earth crises.