Overview
Lanthanum is a soft, ductile rare earth metal that tarnishes rapidly when exposed to air. Discovered in 1839 by Swedish chemist Carl Gustav Mosander, it is the first element in the lanthanide series. Despite its classification, lanthanum lacks f-electrons in its ground state, making it chemically similar to group 3 elements. As one of the more abundant rare earth elements, lanthanum constitutes approximately 0.0018% of the Earth's crust. It's typically extracted from minerals like monazite and bastnäsite through complex ion-exchange and solvent extraction processes. The metal plays a crucial role in modern technology due to its unique electronic configuration and chemical properties.
Physical and Chemical Properties
Lanthanum exhibits typical metallic properties: good electrical and thermal conductivity, malleability, and a bright silvery luster when freshly cut. The metal is soft enough to be cut with a knife and has one of the lowest hardness values among metals. Its density of 6.162 g/cm³ is relatively high but lower than most transition metals. Chemically, lanthanum is highly reactive, quickly forming an oxide layer when exposed to air. It reacts slowly with cold water and vigorously with hot water to form lanthanum hydroxide. The metal dissolves readily in dilute acids and reacts with most nonmetals at elevated temperatures. Lanthanum's +3 oxidation state is exceptionally stable, dominating its chemistry.
Main Applications
The largest application of lanthanum is in petroleum refining catalysts (FCC catalysts), where it improves yields of high-octane gasoline. Lanthanum oxide is crucial in special optical glasses, particularly camera and telescope lenses, due to its high refractive index and low dispersion. In battery technology, lanthanum-nickel alloys are used in nickel-metal hydride (NiMH) rechargeable batteries, particularly in hybrid electric vehicles. The hydrogen storage capability of these alloys makes them valuable for clean energy applications. Lanthanum also finds use in carbon arc lamps, scintillators, and as a dopant in phosphors for lighting and display technologies.
Safety and Storage
Lanthanum metal presents moderate health hazards, primarily as a flammable solid when in powder or thin foil form. The dust can ignite spontaneously in air and reacts violently with oxidizers. Proper personal protective equipment including dust masks and safety goggles should be worn when handling. For storage, lanthanum must be kept under mineral oil or in sealed containers under inert gas (argon or nitrogen) to prevent oxidation. Large quantities should be stored in fireproof cabinets separate from acids and oxidizers. Spills should be collected carefully using non-sparking tools and disposed of as hazardous waste according to local regulations.
B2B Procurement Guide
When procuring lanthanum for industrial applications, purity specifications should be clearly defined based on end-use requirements. Standard commercial purity ranges from 99% to 99.99% (4N). For high-tech applications like optical glass or electronics, higher purity grades (99.995% or better) are typically required. Bulk purchases (100kg+) often qualify for significant discounts, with prices fluctuating based on rare earth market conditions. Suppliers should provide certificates of analysis (COA) and material safety data sheets (MSDS). Due to lanthanum's reactivity, verify packaging integrity - metal ingots should be vacuum-sealed or oil-packed, while powders require double-bagged containment with desiccants.