Introduction
Lanthanum (atomic number 57) is the namesake of the lanthanide series. It is a Light Rare Earth Element (LREE) and one of the most reactive of the group. It is essential in fields ranging from optics to energy storage.
Chemical & Physical Properties
A silvery-white, malleable, and ductile metal. Lanthanum is so soft it can be cut with a knife. It oxidizes rapidly when exposed to air and reacts vigorously with water. Because of this reactivity, pure lanthanum metal is rarely used; it is mostly utilized in its oxide or alloy forms.
Occurrence & Production
Lanthanum is the second most abundant rare earth after cerium. It is a major constituent of primary REE minerals like bastnäsite and monazite. Major production centers are in China, the USA (Mountain Pass), and Australia (Mount Weld).
Key Applications & Uses
- Nickel-Metal Hydride (NiMH) Batteries: A primary use of lanthanum-rich mischmetal (a natural alloy of rare earths) is in the anode of NiMH batteries, which power many hybrid vehicles (like the Toyota Prius) and rechargeable consumer electronics.
- High-Quality Optics: Lanthanum oxide increases the refractive index and lowers the dispersion of glass. It is essential for high-end camera lenses, telescope lenses, and optical fibers.
- Catalysts: Used in fluid catalytic cracking (FCC) in oil refineries to convert crude oil into gasoline.
Future Outlook & Significance
While lithium-ion batteries dominate pure electric vehicles, NiMH batteries using lanthanum remain crucial for hybrid technology. Its indispensable role in high-quality glass ensures stable industrial demand.