Lanthanum(III) chloride

Preparation

Anhydrous lanthanum(III) chloride can be produced by the ammonium chloride route. In the first step, lanthanum oxide is heated with ammonium chloride to produce the ammonium salt of the pentachloride: :La2O3 + 10NH4Cl → 2(NH4)2LaCl5 + 6H2O + 6NH3 In the second step, the ammonium chloride salt is converted to the trichlorides by heating in a vacuum at 350-400 °C: :(NH4)2LaCl5 → LaCl3 + 2HCl + 2NH3

Uses

Lanthanum chloride is also used in biochemical research to block the activity of divalent cation channels, mainly calcium channels. Doped with cerium, it is used as a scintillator material.

In organic synthesis, lanthanum trichloride functions as a mild Lewis acid for converting aldehydes to acetals.

The compound has been identified as a catalyst for the high pressure oxidative chlorination of methane to chloromethane with hydrochloric acid and oxygen. In Fluid Catalytic Cracking (FCC), lanthanum chloride enhances catalysts to convert heavy crude into valuable fuels like gasoline and diesel.

Also used in the field of geology as a very dilute solution, which when combined with the proper acids can help identify small 1% Strontium content in powdered rock samples.

Lanthanum chloride also contributes to environmental remediation by promoting- the catalytic transformation of pollutants, such as nitrogen oxides (NOx), volatile organic compounds (VOCs), sulfur dioxide (SO₂), and phosphate ions, into less harmful products. It can also be commercially viable and significantly outperform conventional materials such as ion exchange resins, activated carbons, and iron oxides in water and wastewater treatment, especially for the removal of anionic pollutants.

References

References

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6. (2007). "Lanthanum trichloride: An efficient Lewis acid catalyst for chemo and regioselective enamination of β-dicarbonyl compounds". Arkivoc.
7. (2007). "Methyl chloride production from methane over lanthanum-based catalysts". J. Am. Chem. Soc..
8. (2014). "The development of FCC catalysts for producing FCC gasoline with high octane numbers". Applied Petrochemical Research.
9. Loewen, Eric. "Lanthanum Chloride in Catalysis: Mechanisms and Applications".
10. (2021). "Critical review on lanthanum-based materials used for water purification through adsorption of inorganic contaminants.". Critical Reviews in Environmental Science and Technology.