Praseodymium . Praseodymium is a chemical element in the periodic table whose symbol is Pr and its atomic number is 59.
Summary
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- 1 Features
- 1 History
- 2 Applications
- 3 Effects of Praseodymium on health
- 4 Environmental Effects of Praseodymium
- 5 Sources
characteristics
Praseodymium is a soft silvery metallic element, and belongs to the group of lanthanides. It is somewhat more resistant to corrosion in air than europium, lanthanum, cerium, or neodymium, but it develops a green oxide layer when it breaks or when exposed to air, exposing more metal to oxidation. For this reason, praseodymium should be stored under a light mineral oil or sealed in glass.
History
The name praseodymium comes from the Greek words prasios didymos, which mean green twin (πρασιος prasios = “green”) (διδυμος didymos = “twin”). Praseodymium and neodymium were discovered together and that is why they were called twins, seeing that it formed a layer of green oxide on contact with air, that color was added to its name. Praseodymium is frequently mispronounced as praseodymium. In 1841, Carl Gustaf Mosander extracted didymium, a rare earth, from lanthanum. In 1874, Per Teodor Cleve concluded that didymium was made of two elements, and in 1879, Paul Emile Lecoq de Boisbaudran isolated a new earth, samarium, from didymium obtained from the mineral samarskite. In 1885, the Austrian chemist Carl Auer von Welsbach separated didymium into two elements, praseodymium and neodymium, which gave salts of various colors. The Czech Leo Moser (owner of Moser Glassware) investigated the use of praseodymium in the coloration of crystals in the late 1920s. The result was a yellow-green crystal, which was named “Prasemit”. However, a similar color could be achieved with colorants that cost only a small fraction of what praseodymium cost in the late 1920s, such that the color was not popular, few pieces were made, and specimens now they are extremely rare. Moser also mixed praseodymium with neodymium to produce the “Heliolite” crystal (“Heliolit” in German), which was more widely accepted. The first commercial use of praseodymium, which continues to this day, is in the form of an orange-yellow ceramic stain, ” As technology advances, it has been found possible to incorporate praseodymium into neodymium-iron-boron magnets, thereby greatly extending the supply of neodymium demand. In this way, the LC is beginning to replace the LCP accordingly.
Applications
- As an alloying agent with magnesium to create the high-strength metals used in aircraft engines. · Praseodymium forms the basis of carbon arc lights that are used in the motion picture industry, for workshop lighting and projector lights. · Praseodymium compounds are used to give glasses and enamels a yellow color. · Praseodymium is used to color cubic zirconia a green-yellow color, to simulate peridot. · Praseodymium is a component of didymium glass, which is used to make certain types of solder and blown glass. Dr. Matthew Sellars of the Laser Physics Center at the Australian National University in Canberra, Australia delayed a pulse of light to a few hundred meters per second using praseodymium mixed with silicate glass. · Nickel-alloyed praseodymium (PrNi5) has such a strong magneto-caloric effect that it has allowed scientists to get within less than one thousandth of a degree of absolute zero.
Health Effects of Praseodymium
Praseodymium is one of the rare chemicals, which can be found at home in equipment such as color televisions, fluorescent lamps, and glass. All rare chemicals have comparable properties. Praseodymium is rarely found in nature, as it occurs in very small amounts. Praseodymium is normally found in only two different types of minerals. The use of praseodymium continues to grow, due to the fact that it is suitable for producing catalysts and for polishing glass.
Praseodymium is primarily dangerous in the work environment, due to the fact that moisture and gases can be inhaled from the air. This causes pulmonary embolisms, especially during long-term exposure. Praseodymium can be a threat to the liver when it accumulates in the human body.
Environmental Effects of Praseodymium
Praseodymium is released into the environment in many different places, mainly by oil-producing industries. It can also enter the environment when household equipment is thrown away. Praseodymium will gradually accumulate in soil and soil waters and this will eventually lead to increased concentration in humans, animals, and soil particles. In aquatic animals, praseodymium causes damage to cell membranes, which has several negative influences on reproduction and functions of the nervous system.
