What are rare-earth elements and why is everyone looking for them?, Pg9

Key Highlights:

• Rare-earth elements (REEs) are a set of 17 metallic elements crucial for various technologies.
• These elements are difficult and expensive to separate due to their dispersed nature and similar chemical properties.
• REEs are essential for high-performance magnets, specialized lighting, catalysts, and electronics.
• China dominates the REE refining and magnet production, accounting for 91% and 94% of global production, respectively.
• Japan plans to excavate REE-rich mud from underwater off Minamitori Island in early 2026.

Detailed Insights:

• Rare-earth elements include the 15 lanthanides, scandium, and yttrium, known for their unique electrical, magnetic, and optical properties.
• The term "rare earth" is historical, referring to the oxide form of these elements, which were initially difficult to isolate.
• Neodymium-iron-boron magnets, the most common type using REEs, are vital in motors and generators.
• REEs like europium and terbium are used in phosphors, while neodymium and erbium are used in lasers and optical devices.
• The localized 4f electrons in REE atoms contribute to strong magnetic moments and stability in permanent magnets.
• Extracting and processing REEs involves mining, beneficiation, chemical cracking, leaching, and solvent extraction.
• Solvent extraction is used to separate individual REEs due to their similar chemical behavior.
• The REE industry faces environmental challenges, including radioactive waste from thorium and uranium and hazardous waste from acids and bases.
• Global reserves of REEs exceed 90 million tonnes, with China holding the largest reserves at 44 million tonnes.
• Countries are focusing on building refining and magnet-making capacity to reduce dependence on China.

Scientific/Technical Concepts Involved:

• Lanthanides: A series of 15 metallic chemical elements with atomic numbers 57 through 71.
• Phosphors: Substances that emit light when irradiated, often incorporating rare-earth elements.
• Magnetocrystalline anisotropy: The property that aligns magnetic moments with a crystal's preferred direction.
• Solvent extraction: A technique used to separate individual rare-earth elements based on their differing affinities for organic solvents.