Lanthanum oxide, molecular formula La2O3, molecular weight 325.8091. Mainly used for manufacturing precision optical glass and optical fibers.
Chemical property
Slightly soluble in water and easily soluble in acids to form corresponding salts.
Exposed to the air, it is easy to absorb carbon dioxide and water, gradually turning into lanthanum carbonate.
The burning lanthanum oxide combines with water to release a large amount of heat.
physical property
Appearance and properties: White solid powder.
Density: 6.51 g/mL at 25 ° C
Melting point: 2315 ° C, boiling point: 4200 ° C
Solubility: Soluble in acids and ammonium chloride, insoluble in water and ketones.
Production method
1. The raw material for the extraction method is a rare earth nitrate solution after cerium removal, which contains approximately 50% La2O3, trace amounts of CeO2, 116-7% Pr6O5, and 30% Nd2O3. Compounded into Σ A rare earth nitrate solution with a concentration of 320-330g/L of RxOy was extracted and separated from other rare earths using a neutral phosphine extractant, dimethyl heptyl methylphosphonate (P350), in a P350 kerosene system for 35-38 stages of extraction. The residual solution containing lanthanum was neutralized with ammonia, precipitated with oxalic acid, and then filtered and burned to obtain a finished product of lanthanum oxide. Extracted from lanthanum phosphate cerium ore or prepared by burning lanthanum carbonate or nitrate. It can also be obtained by heating and decomposing the oxalate of lanthanum.
2. Place La (OH) 3 in a platinum crucible, dry at 200 ℃, burn at 500 ℃, and decompose over 840 ℃ to obtain lanthanum oxide.
Application
Mainly used for manufacturing precision optical glass and optical fibers. Also used in the electronic industry as ceramic capacitors and piezoelectric ceramic additives. It is also used as a raw material for the production of lanthanum borate and as a catalyst for petroleum separation and refining.
Application field: Mainly used for manufacturing special alloy precision optical glass, high refractive optical fiber board, suitable for making cameras, cameras, microscope lenses, and prisms for advanced optical instruments. It is also used in the manufacturing of ceramic capacitors, piezoelectric ceramic dopants, and X-ray luminescent materials such as lanthanum bromide powder. Extracted from lanthanum phosphate cerium ore or obtained by burning lanthanum carbonate or nitrate. It can also be obtained by heating and decomposing the oxalate of lanthanum. Used as a catalyst for various reactions, such as catalytic oxidation of carbon monoxide when doped with cadmium oxide, and catalytic hydrogenation of carbon monoxide to methane when doped with palladium. Lanthanum oxide infiltrated with lithium oxide or zirconia (1%) can be used to manufacture ferrite magnets. It is a highly effective selective catalyst for the oxidative coupling of methane to produce ethane and ethylene. Used to improve the temperature dependence and dielectric properties of barium titanate (BaTiO3) and strontium titanate (SrTiO3) ferroelectrics, as well as to manufacture fiber optic devices and optical glasses.
Post time: Aug-08-2023