Recycling of Rare Earth Elements: From E-Waste to Stereoselective Catalytic Reactions

• Published in: ChemSusChem 2024-10, p.e202401787
• Main Authors: Donato, Emanuela, Medici, Fabrizio, Chiroli, Valerio, Puglisi, Alessandra, Rogoli, Clemens, Fröhlich, Peter, Bertau, Martin, Zanoni, Giuseppe, Benaglia, Maurizio
• Format: Article
• Language: English
• ISSN: 1864-5631; 1864-564X; 1864-564X
• DOI: 10.1002/cssc.202401787

Raw mixtures of Rare Earths Elements, REE, recovered by E-waste, were used as catalysts to promote the (stereoselective) synthesis of highly valuable compounds. Y2O3, the major species that is recovered by the E-waste, can be easily converted into the catalytically active Y(OTf)3 that is able to efficiently promote the Michael addition of indoles to benzylidene malonates and the stereoselective Diels-Alder cycloaddition between cyclopentadiene and 4-(S)-3 acryloyl 4-tert-butyl 2-oxazolidinone. Additionally, the raw mixtures were immobilized onto silica and used to construct packed reactors, resulting in values for Productivity and Space-Time Yields that were significantly higher than those of the corresponding batch conversions. Notably, the prepared cartridge employed in the model Michael reaction maintained its catalytic efficiency for more than 4 days of continuous running.