Recovery of red (Y2O3:Eu3+), Blue(Sr,Ca,Ba)10(PO4)6 Cl2:Eu2+ and green(LaPO4:Tb3+,Ce3+) rare earth phosphors from waste phosphor sludge by liquid/liquid eztraction
A new method for recovery of red (Y2O3:Eu3+), blue (Sr,Ca,Ba)10(PO4)6Cl2:Eu2+ and green (LaPO4:Tb3+,Ce3+) rare earth phosphors from waste phosphor sludge by liquid/liquid extraction is proposed in this paper. At first, the recommended pretreatment process is effective to remove the adhesive binder such as Al2O3 and the other impurities from the spent florescent powder complex, which including treatment by nitric acid solution of pH 2 for 1-5 minutes, by sodium hydroxide solution of pH 12.5 for 12minutes and rinsing by 99.5％ ethanol and distilled water. The subsequent separation for dried florescent powder was carried out in the heptane/ DMF (N, N-Dimethylformamide) system in presence of DAA (laurylamine) surfactant. Through two steps extraction process with different DAA concentration. Satisfactory separation results have been achieved; the grade and recovery of recovered red, blue and green product reach 86.0％ and 80.3％, 74.8％ and 95.6％, 81.2％ and 79.5％, respectively. This invention provides a new possibility for the recycling of valuable rare earth phosphor from spent fluorescent lamps in the future.
Rare earth phosphor Separation Recovery Liquid/liquid eztraction
Mei,Guangjun Xie, Kefeng
School of resource and environmental engineering, Wuhan University of technology Wuhan, China
国际会议
上海
英文
4674-4679
2008-05-16（万方平台首次上网日期，不代表论文的发表时间）