The chemistry and scope of lanthanum and lanthanum compounds is reviewed here. We manufacture all these compounds and in most instances with these rare earth products , it is important to know the method of manufacture, solubilities, assays and trace impurities.
Rare earth compounds were named not
because the individual rare earth elements are rare but because
each individual rare earth element rarely exists as a single
element but a s a mixture of rare earth elements. The word
lanthanum comes from the Greek λανθανω [lanthanō] =
to lie hidden. Lanthanum was discovered in 1839 by Swedish
chemist Carl Gustav Mosander, when he partially decomposed a
sample of cerium nitrate by heating and treating the resulting
salt with dilute nitric acid. From the resulting solution, he
isolated a new rare earth he called lantana. Lanthanum
was isolated in relatively pure form in 1923.
The composition of monozite ore is the basis for rare
earth impurities found in lanthanum compounds and the level of
impurities is directly related to the separation and source of
these ores. Lanthanum is
most commonly obtained from monazite and bastnäsite. The mineral
mixtures are crushed and ground. Monazite, because of its
magnetic properties can be separated by repeated electromagnetic
separation. After separation, it is treated with hot
concentrated sulfuric acid to produce water-soluble sulfates of
rare earths. The acidic filtrates are partially neutralized with
sodium hydroxide to pH 3-4. Thorium precipitates out of solution
as hydroxide and is removed. After that the solution is treated
with ammonium oxalate to convert rare earths in to their
insoluble oxalates. The oxalates are converted to oxides by
annealing. The oxides are dissolved in nitric acid that excludes
one of the main components, cerium, whose oxide is insoluble in
HNO3. Lanthanum is separated as a double salt with
ammonium nitrate by crystallization. This salt is relatively
less soluble than other rare earth double salts and therefore
stays in the residue.
The most efficient separation routine for lanthanum salt from the
rare-earth salt solution is however ion exchange. In this
process, rare-earth ions are adsorbed onto suitable ion-exchange
resin by exchange with hydrogen, ammonium or cupric ions present
in the resin. The rare earth ions are then selectively washed
out by suitable complexing agent, such as ammonium citrate or
nitrilotracetate. Lanthanum can also be separated from solution
of rare earth nitrates by liquid-liquid extraction with a
suitable organic liquid, such as tributyl phosphalate.
Currently, the most widely used extractant for the purification
of lanthanum and the other lanthanides is the 2-ethylhexyl ester
of 2-ethylhexylphosphonic acid; this has better handling
characteristics than the previously used bis-2-ethylhexyl
phosphate.
Level of
impurities:
99.9%(REO)
1000ppm total rare
earth oxide impurities
99.99%(REO)
100ppm total rare
earth oxide impurities
99.999%(REO)
10ppm total rare
earth oxide impurities
99.9999%(REO)
1ppm total rare
earth oxide impurities
For a certificate
of analysis for any of these products ordered contact:
techservice@rareearthproducts.com
Lanthanum chloride, bromide and nitrates are isolated as the hexahydrates and are very soluble in water. Anhydrous halides are also available. Lanthanum acetate is somewhat soluble in water. (It is important to work with the manufacturer of your rare earth products because in the case of acetates the solubility varies widely depending on the method of manufacture and reaction conditions.
A new exciting lanthanum compound is lanthanum trifluoroacetate which is very soluble in water and has new uses as a catalyst in organic synthesis. Lanthanum oxalate, carbonate and sulfate are insoluble in water and exist as a defined hydrate. These compounds can also be dehydrated.
Another example of purchasing rare earth compounds from a known manufacturer is lanthanum fluoride. The rare earth fluorides are used in advanced material films, lens and glasses. In virtually all applications the fluoride should be carbonate free. Rare Earth Products, Inc. uses a proprietary process to make carbonate free rare earth fluorides.
Rare earth Products, Inc makes the most extensive list of rare earth metal beta diketonates. These organometallic compounds are used for MOCVD, spin coating, catalysts and NMR shift reagents to name a few advanced applications. The compounds offered include rare earth metal complexes with
acetylacetonate or 2,4-pentanedionate ACAC
hepatfluorodimethyloctanedionate FOD
hexafluoracetylacetonate HFAC
tetrametylheptanedionate TMHD
trifluroacetylacetonate TFAC
chiral ligands OPT etc.
Most of these compounds are used because of the physical vapor pressure, volatility and organic solvent solubility. Contact our technical service department to get physical data such as melting points, sublimation temperatures, solubility, boiling points, etc - techservice@rareearthproducts.com.
Rare Earth Products, Inc also manufactures the organic soluble compounds lanthanum 2-ethylhexanoate and lanthanum cyclohexanebutyrate. These metal organic compounds are soluble in organic solvents. We can also custom synthesize various rare earth p compounds by adding various ligands, dehydrating and coordinating various organic solvents to enhance non polar solubility. Contact techservice@rareearthproducts.com.
The intermetallics lanthanum sulfide, lanthanum selenide and lanthanum telluride are available upon request. Lanthanum trifluoromethanesulfonate or lanthanum triflate is available and useful as a Friedel -Crafts catalyst as the anhydrous salt or the hydrate. A new compound lanthanum thenoyltrifluoroacetonate is used as a thermal laser dye.
Rare Earth Compounds Lanthanum
| L, 5725 | Lanthanum acetate hydrate, 99.99% (REO) | [ 2572-92-0 ] | 25gm | $26.00 | |
| 100gm | $51.00 | ||||
| L, 5703K | Lanthanum acetylacetonate, 99.9% (REO) | [ 14284-88-9 ] | 25gm | $32.00 | |
| 100gm | $119.00 | ||||
| L, 5714 | Lanthanum bromide hydrate, 99.99% (REO) | 25gm | $26.00 | ||
| 100gm | $77.00 | ||||
| L, 5716 | Lanthanum carbonate, 99.9% (REO) | [ 6487-39-4 ] | 25gm | $26.00 | |
| 100gm | $69.00 | ||||
| L, 5726 | Lanthanum carbonate, 99.99% (REO) | [ 6487-39-4 ] | 25gm | $27.00 | |
| 100gm | $102.00 | ||||
| L, 5712 | Lanthanum chloride hexahydrate, 99.999% (REO) | [ 17272-45-6 ] | 25gm | $26.00 | |
| 100gm | $51.00 | ||||
| L, 5723 | Lanthanum chloride, anhydrous, 99.9% (REO) | [ 10099-58-8 ] | 25gm | $41.00 | |
| 100gm | $153.00 | ||||
| L, 5707 | Lanthanum cyclohexanebutyrate, 99.9% (REO) | 5gm | $110.00 | ||
| 25gm | $519.00 |