Praseodymium is a chemical element with symbol Pr and atomic number 59.
- In combination with neodymium, another rare earth element, praseodymium is used to create high-power magnets notable for their strength and durability.
- As an alloying agent with magnesium to create high-strength metals that are used in aircraft engines; yttrium and neodymium are also viable substitutes.
- Praseodymium is present in the rare earth mixture whose fluoride forms the core of carbon arc lights which are used in the motion picture industry for studio lighting and projector lights.
- Praseodymium compounds give glasses and enamels a yellow color.
- Praseodymium is used to color ceramics yellow.
- Praseodymium is a component of didymium glass, which is used to make certain types of welder’s and glass blower’s goggles.
- Silicate crystals doped with praseodymium ions have been used to slow a light pulse down to a few hundred meters per second.
- Praseodymium alloyed with nickel (PrNi5) has such a strong magnetocaloric effect that it has allowed scientists to approach within one thousandth of a degree of absolute zero. In general, most alloys of the cerium group rare earths (lanthanum through samarium) with 3d transition metals give extremely stable magnets that are often used in small equipment, such as motors, printers, watches, headphones, loudspeakers, and magnetic storage.
- Doping praseodymium in fluoride glass allows it to be used as a single mode fiber optical amplifier.
- Praseodymium oxide in solid solution with ceria, or with ceria-zirconia, have been used as oxidation catalysts.
- Pr3+ ions are used as activators in some red, green, blue, and ultraviolet phosphors.
- The early lanthanides act as essential cofactors for the methanol dehydrogenase of the methanotrophic bacterium Methylacidiphilum fumariolicum SolV, for which lanthanum, cerium, praseodymium, and neodymium alone are about equally effective. Praseodymium is otherwise not known to have a biological role in any other organisms, but is not very toxic either. Intravenous injection of rare earths into animals has been known to impair liver function, but the main side effects from inhalation of rare earth oxides in humans come not from the rare earths themselves but from the radioactive thorium and uranium impurities, as the rare earths tend to occur together with these elements
Source: Wikipedia, https://en.wikipedia.org/wiki/Praseodymium#Applications