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LANTHANUM Suppliers list
Company Name: Mainchem Co., Ltd.
Tel: +86-0592-6210733
Products Intro: Product Name:LANTHANUM
Company Name: J & K SCIENTIFIC LTD.  
Tel: 400-666-7788 +86-10-82848833
Products Intro: Product Name:Lanthanum powder (99.9% REO)
Purity:(99.9% REO) Package:10g;50g
Company Name: Alfa Aesar  
Tel: 400-610-6006; 021-67582000
Products Intro: Product Name:LanthanuM sputtering target, 76.2MM dia x 1.59MM thick
Package:1each Remarks:046064
Company Name: Energy Chemical  
Tel: 021-58432009 / 400-005-6266
Products Intro: Product Name:LanthanuM rod, 6.35MM (0.25in) dia, 99.9% (REO)
Purity:99.9%(REO) Package:100g,25g
Company Name: JinYan Chemicals(ShangHai) Co.,Ltd.  
Tel: 13817811078,021-50426030
Products Intro: CAS:7439-91-0
LANTHANUM Chemical Properties
Melting point 920 °C(lit.)
Boiling point 3464 °C(lit.)
density 6.19 g/mL at 25 °C(lit.)
form slugs
color Silver-white
Specific Gravity6.19
resistivity54 μΩ-cm
Water Solubility slowly decomposes in H2O; readily attacked by mineral acids [MER06]
Sensitive Air & Moisture Sensitive
Merck 13,5379
CAS DataBase Reference7439-91-0(CAS DataBase Reference)
Safety Information
Hazard Codes F,T
Risk Statements 11-34-23/24/25-14/15
Safety Statements 26-27-36/37/39-45-33-16-23-43-Neverusewater.
RIDADR UN 3264 8/PG 3
WGK Germany 3
HazardClass 4.1
PackingGroup III
MSDS Information
SigmaAldrich English
ACROS English
ALFA English
LANTHANUM Usage And Synthesis
HistoryLanthanum was isolated from cerium nitrate in 1839 by Mosander. The element in its oxide form was called “lanthana” meaning “hidden”. Although the electron configuration of the element shows a vacant 4f orbital and, therefore, does not belong to the “true rare-earth elements,” the metal exhibits striking similarities to other rare-earths. In nature, lanthanum never occurs in free state and is always found associated with other rare-earth metals. The principal minerals are monazite and bastnasite. Its concentration in the earth’s crust is estimated to be 30 mg/kg. Lanthanum as a pure metal has limited applications. However, in the form of alloys, the metal has several metallurgical applications. When alloyed with iron, chromium, nickel, and molybdenum, it improves resistance of these metals to oxidation. It also improves the impact strength, fluidity, ductility and other mechanical properties of the alloys. The pure metal is used only for research.
Production MethodsExtraction of lanthanum from monazite is discussed below first, followed by that from bastnasite. The mineral mixtures are crushed and ground.After its separation the mineral is treated with hot concentrated sulfuric acid, which converts thorium, lanthanum, and rare-earth metals present into their sulfates. Alternatively, thorium may be precipitated as pyrophosphate by adding sodium pyrophosphate to the acid solution. The solution after removal of thorium is treated with ammonium oxalate. This converts all lanthanide elements in the ore into their insoluble oxalate salts. The oxide mixture is, therefore, treated with dilute nitric acid to dissolve lanthanum oxide and other rare-earth oxides to separate them from cerium. Lanthanum is separated from this cerium-free rareearth mixture as a double salt with ammonium nitrate by crystallization. The lanthanum-ammonium double salt is relatively less soluble than other rareearth double salts and stays in the most insoluble fraction.
Chemical Propertiessolid
HistoryMosander in 1839 extracted a new earth lanthana, from impure cerium nitrate, and recognized the new element. Lanthanum is found in rare-earth minerals such as cerite, monazite, allanite, and bastnasite. Monazite and bastnasite are principal ores in which lanthanum occursin percentages up to 25 and 38%, respectively. Misch metal, used in making lighter flints, contains about 25% lanthanum. Lanthanum was isolated in relatively pure form in 1923. Ion-exchange and solvent extraction techniques have led to much easier isolation of the so-called “rare-earth” elements. The availability of lanthanum and other rare earths has improved greatly in recent years. The metal can be produced by reducing the anhydrous fluoride with calcium. Lanthanum is silvery white, malleable, ductile, and soft enough to be cut with a knife. It is one of the most reactive of the rare-earth metals. It oxidizes rapidly when exposed to air. Cold water attacks lanthanum slowly, and hot water attacks it much more rapidly. The metal reacts directly with elemental carbon, nitrogen, boron, selenium, silicon, phosphorus, sulfur, and with halogens. At 310°C, lanthanum changes from a hexagonal to a face-centered cubic structure, and at 865°C it again transforms into a body-centered cubic structure. Natural lanthanum is a mixture of two isotopes, one of which is stable and one of which is radioactive with a very long halflife. Thirty other radioactive isotopes are recognized. Rareearth compounds containing lanthanum are extensively used in carbon lighting applications, especially by the motion picture industry for studio lighting and projection. This application consumes about 25% of the rare-earth compounds produced. La2O3 improves the alkali resistance of glass, and is used in making special optical glasses. Small amounts of lanthanum, as an additive, can be used to produce nodular cast iron. There is current interest in hydrogen sponge alloys containing lanthanum. These alloys take up to 400 times their own volume of hydrogen gas, and the process is reversible. Heat energy is released every time they do so; therefore these alloys have possibilities in energy conservation systems. Lanthanum and its compounds have a low to moderate acute toxicity rating; therefore, care should be taken in handling them. The metal costs about $2/g (99.9%).
UsesLanthanum is the first element in the rare earth or Lanthanide series. It is the model for all the other trivalent rare earths. After Cerium, it is the second most abundant of the rare earths.
Lanthanum-rich Lanthanide compounds have been used extensively for cracking reactions in FCC catalysts, especially to manufacture high-octane gasoline from heavy crude oil. 
Lanthanum-Rich Rare Earth metals play the important roles in hydrogen storage batteries.
It is utilized in green phosphors based on the phosphate (La0.4Ce0.45Tb0.15)PO4;in laser crystals based on the Yttrium-Lanthanum-Fluoride (YLF) composition.
Lanthanum Metal is the very important raw materials in producing Hydrogen Storage Alloys for NiMH batteries, and is also used to produce other pure Rare Earth metals and specialty alloys. Small amounts of Lanthanum added to Steel improves its malleability, resistance to impact, and ductility; Small amounts of Lanthanum are present in many pool products to remove the Phosphates that feed algae. Lanthanum Metal can be further processed to various shapes of ingots, pieces, wires, foils, slabs, rods, discs and powder.
Purification MethodsIt is a shiny metal that slowly tarnishes in air due to oxidation. It slowly decomposes by H2O in the cold and more rapidly on heating to form the hydroxide. The metal is cleaned by scraping off the tarnished areas until the shiny metal is revealed and stored under oil or paraffin. It burns in air at 450o. It exists in three forms: -form, -form and -form with transition temperatures of 310o and 864o, respectively. [Spedding et al. Ind Eng Chem 44 553 1952.]
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