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Comprehensive CeMgAl11O19:Tb3+(CTMA)disintegration via alkaline fusion was discussed. The rare earth(RE) elements in CTMA were dissolved by HCl completely after alkaline fusion. Relationships between the alkaline fusion temperature and various properties of the compounds were examined by various techniques to elucidate their roles in the expected CTMA disintegration.X-ray diffraction(XRD) analysis indicates the phase transformation sequence. A scientific hypothesis of crystal structure disintegration presents that sodium ions substitute for the europium and barium ions in the mirror plane and magnesium ions in the spinel block successively, resulting in that more oxygen vacancies and interstitial sodium ions appear. The unit cell [P63/mmc(194)] breaks from the mirror plane. Then it is decomposed into Na Al O2, and magnesium, cerium, and terbium ions combine with free OH-into Mg O, Tb2O3 and CeO2;Tb2O3 and CeO2 change into Ce0.6Tb0.4O2-x. In the end, the rare earth oxide is recycled easily by the acidolysis. The mechanism provides fundamental basis for recycling of REEs from waste phosphors.
Comprehensive CeMgAl11O19: Tb3 + (CTMA) disintegration via alkaline fusion was discussed. The rare earth (RE) elements in CTMA were dissolved by HCl completely after alkaline fusion. Relationships between the alkaline fusion temperature and various properties of the compounds were examined by various techniques to elucidate their roles in the expected CTMA disintegration. X-ray diffraction (XRD) analysis indicates the phase transformation sequence. A scientific hypothesis of crystal structure disintegration presents that sodium ions substitute for the europium and barium ions in the mirror plane and magnesium ions in the spinel block successively, resulting in that more oxygen vacancies and interstitial sodium ions appear. The unit cell [P63 / mmc (194)] breaks from the mirror plane. Then it is decomposed into NaAl O2, and magnesium, cerium, and terbium ions combine with free OH-into MgO, Tb2O3 and CeO2; Tb2O3 and CeO2 change into Ce0.6Tb0.4O2-x. In the end, the rare earth oxide is recycled eas ily by the acidolysis. The mechanism provides fundamental basis for recycling of REEs from waste phosphors.