Rare-earth elements (REEs) are essential metals for the design and development of sustainable energy applications, Recycling these elements from waste streams enriched in them is crucial for securing an independent ...Rare-earth elements (REEs) are essential metals for the design and development of sustainable energy applications, Recycling these elements from waste streams enriched in them is crucial for securing an independent future supply for sustainable applications, This study compares the mechanisms of mechan- ical activation prior to a hydrometallurgical acid-leaching process and a solvometallurgical mechanochemical leaching process for the recovery of REEs from green lamp phosphor, LaPO4:Ce3+, Th3+, After 60 min of processing time, the REE leaching rates showed a significant enhancement of 60% after cycled mechanical activation, and 98% after the combined mechanochemical leaching process, High-resolution transmission electron microscopy (HR-TEM) imaging disclosed the cause for the improved REE leaching rates: The improved leaching and leaching patterns could he attributed to changes in the crystal morphology from monocrystalline to polycrystalline, Reduction of the crystallite size to the nanoscale in a polycrystalline material creates irregular packing of chemical units, resulting in an increase in defect-rich grain boundaries in the crystals, which enhances the leaching process, A solvometallurgical method was developed to combine the mechanical activation and leaching process into a single step, which is beneficial for operational cost, This results in an efficient and simple process that provides an alternative and greener recycling route for lamp phosphor waste,展开更多
基金supported by KU Leuven (GOA/13/008 and IOFKP RARE3)FWO-Flanders for a SB PhD fellowship (1S23518N)the European Research Council (ERC) under the European Union’s Horizon 2020 Research and Innovation Programme: Grant Agreement 694078-Solvometallurgy for critical metals (SOLCRIMET)
文摘Rare-earth elements (REEs) are essential metals for the design and development of sustainable energy applications, Recycling these elements from waste streams enriched in them is crucial for securing an independent future supply for sustainable applications, This study compares the mechanisms of mechan- ical activation prior to a hydrometallurgical acid-leaching process and a solvometallurgical mechanochemical leaching process for the recovery of REEs from green lamp phosphor, LaPO4:Ce3+, Th3+, After 60 min of processing time, the REE leaching rates showed a significant enhancement of 60% after cycled mechanical activation, and 98% after the combined mechanochemical leaching process, High-resolution transmission electron microscopy (HR-TEM) imaging disclosed the cause for the improved REE leaching rates: The improved leaching and leaching patterns could he attributed to changes in the crystal morphology from monocrystalline to polycrystalline, Reduction of the crystallite size to the nanoscale in a polycrystalline material creates irregular packing of chemical units, resulting in an increase in defect-rich grain boundaries in the crystals, which enhances the leaching process, A solvometallurgical method was developed to combine the mechanical activation and leaching process into a single step, which is beneficial for operational cost, This results in an efficient and simple process that provides an alternative and greener recycling route for lamp phosphor waste,