Monazite ytterbium

Ytterbium occurs along with other rare earths in a number of rare minerals. It is commercially recovered principally from monazite sand, which contains about 0.03%. Ion-exchange and solvent extraction techniques developed in recent years have greatly simplified the separation of the rare earths from one another. 

Ytterbium occurs in minerals euxenite, a complex titanium niobotantalate gadolinite, a rare earth iron beryUium sdicate monazite, a thorium-rare earth phosphate and xenotime, also a rare earth-thorium phosphate. Abundance of ytterbium in the earth s crust is estimated to be 3.2 mg/kg. 

The principal sources of ytterbium are euxenite, gadolinite, monazite, and xenotime. the latter being the most important. Ytterbium is separated from a mixture of yttrium and the heavy Lanthanides by using the sodium amalgam reduction technique. Ytterbium metal is obtained by heating a mixture of lanthanum metal and ytterbium oxide under high vacuum. The ytterbium sublimes and is collected on condenser plates whereas the lanthanum is oxidized to the sesquioxide. 

Ytterbium is one of the more common lanthanoids. It is thought to have an abundance of about 2.7 to 8 parts per million in Earth s crust. That makes it somewhat more common than bromine, uranium, tin, and arsenic. Its most common ore is monazite, which is found in beach sands in Brazil, India, and Florida, among other places. Monazite typically contains about 0.03 percent ytterbium. 

The commercially important samarium-containing minerals are treated with concentrated sulfuric acid or, in the case of monazite, with a solution of sodium hydroxide (73%) at approximately 40°C (104°E) and under pressure. The element is separated from the solutions via solvent extraction or ion exchange. Sm salts are weakly yellow and may exhibit ion emission. Sm ions show luminescence and are sometimes used to generate lasers. Samarium is used in the manufacture of headphones and tape drivers, see ALSO Cerium Dysprosium Erbium Europium Gadolinium Holmium Lanthanum Lutetium Neodymium Praseodymium Promethium Terbium Ytterbium. 

---