Dysprosium, Research Paper Example

Abstract

The chemical element Dysprosium has sign Dy with atomic number 66. Its color is metallic silver and a rare earth element. Dysprosium is one of 15 chemically similar elements identified as the lanthanoid or rare earth elements. The term rare earth is a misconception basically because some are not rare. The minerals from which they are produced, and the properties and uses they have in common, are discussed under lanthanoids. This paper will illustrate the discovery and further advancement, structure, fundamental characteristic, uses, and Safety Measures.

The amount of dysprosium in the average person is small and so far no one has examined diet for dysprosium content. The metal has no biological character and, judging by the data of other lanthanoids, the levels will be highest in bone, with smaller amounts being present in the liver and kidneys. Dysprosium is not taken up by plant roots so little gets into the main food chain. It is difficult to ascertain how much we take in every day but it is probably less than a microgram.

Soluble dysprosium salts, such as chloride and nitrate, are mildly toxic by consumption, but insoluble salts are non toxic. Based on the toxicity of dysprosium chloride to mice it can be calculated that a dose of 500g or more would be needed to put a person’s life at risk.

Discovery and development of the material

Dysprosium was discovered in 1886 by Paul Emile Lecoq de Boisbaudran in Paris. The strategies that led to this are part of a sequence of events which started with the discovery of unclean yttrium oxide from which erbium and terbium were later to be separated. In 1878-79, erbium was also found to be harboring two other rare earth oxides: those of holmium and thulium. But this was not the end of the story because de Boisbaudran, working on the holmium oxide, divided from it yet another rare earth oxide, that of dysprosium.

His process involved dissolving the oxide in acid and then adding up ammonia to precipitate the hydroxide. He continued this sequence 32 times, and followed them with 26 precipitations of the insoluble salt terbium oxalate from solution. This boring process potentially yielded the new rare earth dysprosium. He named it thus because it really had been dysprositos. He later showed that the separation had been carried out on the marble slab of his fireplace at home. Maybe, because of the barriers in protecting the first sample of dysprosium, this was one of the few elements whose discovery was not questioned.

Natural samples of dysprosium were inaccessible till Frank Spedding and co-workers at Iowa State University developed the approach of ion-exchange chromatography around 1950. From then on it was possible to separate the rare earth elements in a trustworthy and efficient manner.

Structure and fundamental characteristics

Primarily, the Dysprosium can be obtained from monazite sand which is the mixture of numerous phosphates. In the commercial origin of yttrium, this metal is collected as a byproduct. To isolate dysprosium the excessive/unwanted metals could be removed by floatation process or magnetic process. With the help of ion exchange displacement process, it is easier to separate dysprosium from other rare earth metals. To form dysprosium fluoride DyF3 or dysprosium chloride DyCl3, the producing dysprosium ions can react with either fluorine or chlorine. In the following reactions these compounds can be decreased by using either calcium or lithium metals (Heiserman, 1992, pg. 236).

3Ca+2DyF 3 ——2 Dy + 3 CaF2

3 Li+DyCl3 ——Dy + 3 Li Cl

“The components are placed in a tantalum crucible and fired in a helium atmosphere. As the reaction progresses, the resulting halide compounds and molten dysprosium separate due to differences in density. When the mixture cools, the dysprosium can be cut away from the impurities” (Heiserman,1992, pg 238). The most special property is managed by one type of dysprosium alloy, known as Terfenol.D. This noticeably lengthens and shortens when revealed to a magnetic field. Dysprosium may possibly be the element with the highest consistent atomic number: 66. Nuclear theory suggests that all elements above this are not stable and that for these heavier compounds, where we regard them as stable, we only do so because their radioactive half lives are so extremely long.

It is chemical element:

Data file

Chemical symbol__________ Dy

Atomic Number____________66

Atomic Weight____________162.50

Melting Point____________ 1412 degree centigrade

Boiling Point______________2560 degree centigrade

Density__________________8.6/cm cube

Oxide__________________ Dy2O3

Dysprosium is a vibrant, silvery metal and a member of the lanthanoid group of the periodic table of the compounds. It is gradually oxidized by oxygen, responds with cold water, and rapidly dissolves in acids. It is slowly oxidized by oxygen, reacts with cold water, and instantly dissolves in acids. Its recommended oxidation state is +3 as in its salts such as DyF3, which is green, and in solution it exists as the yellow Dy3+ ion, around which cluster as many as nine water molecules.

There are 36 known isotopes of dysprosium with mass numbers 138 to 173, and 12 known isomers. In mineral deposits there are seven naturally happening isotopes: dysprosium -164 constitutes 28%, dysprosium -162 25.5%, dysprosium -163 25%, dysprosium-156 .06%. All stable except dysprosium -156 which is radioactive with a half-life of 10^18 years. The next longest lived radioactive isotope is dysprosium -154 with a half life of 3 million years.

Dysprosium have found in minerals that consist of all the rare earth elements. The most significant ores are monazite and bastnasite. Even though it is not a vital component of either, it is present in extractable amounts (China is the major producer of this element). Dysprosium is also found in several other minerals such as xenotime, fergusonite, gadolinite, euxenite, and polycrase. World production is around 2000 tons per year, and it is available as dysprosium metal itself and dysprosium oxide (Humphries, 2011).

The metal is delivered by heating dysprosium fluoride with calcium. It can be cut with a knife and it machines with no sparking. As a natural metal, dysprosium is worthless, because it rapidly corrodes. Dysprosium discovers itself in several principles along with other lanthanoid elements. Some is used in producing alloys for the best kinds of long lasting magnets, such as the alloy with neodymium, iron, and boron. Dysprosium has the biggest magnetic moments of any elements.

Uses of the Material

Dysprosium’s most helpful known use is in halide discharge lamps where dysprosium iodide is used to get very extreme light. The iodide dissociates into dysprosium atoms in the lamps hot centre and they absorb energy and re-emit it in the form of noticeable light in the spectral regions 470-500 nm and 570-600nm, making it appear almost like white light.

Dysprosium is used in nuclear reactors a s cermets, which is there to absorb neutrons and so cools the chain response that is providing the energy. It makes good cermets because it neither swells not contracts under prolonged neutron bombardment. Another use in the field of radioactivity is in dosimeters for tracking exposure to ionizing radiation. When dysprosium doped crystals of calcium sulfate or calcium fluoride are revealed to disastrous radiation this excites the dysprosium atoms which then luminese and this concludes the degree of exposure the dosimeter has been subjected to.

Dysprosium oxide is used as a doping in special ceramics, such as barium titanium oxide, which are used to produce high capacitance, small size capacitors for electronic applications. Other uses of dysprosium are in erasable optical laser-read discs, and in temperature compensating capacitors.

“Dysprosium is used in dosimeters for measuring ionizing radiation. Crystals of calcium sulfate or calcium fluoride are doped with dysprosium. When these crystals are exposed to radiation, the dysprosium atoms become excited and luminescent. The luminescence can be measured to determine the degree of exposure to which the dosimeter has been subjected” (Emsley, 2001, pg. 129-132).

Dysprosium oxide is inserted to the specialized ceramic used to make capacitors. These are devices that can store electric charge and are extensively used in electronic circuits. Nuclear reactors naturally produce high speed neutrons, but some of these must be absorbed to control the nuclear reaction. Alternatively, there would be a nuclear explosion. Dysprosium oxide is one of the compounds used in the control rods for some nuclear reactors because it has a high melting point and is very good at ingesting neutrons.

A type of lamp called medium source rare earth lamp, or MSR lamp for short, contains dysprosium and holmium substances mixed with other compounds. MSR lamps produce light with a good balance of color. They are often used to light movie sets and theater phases, so scenes look natural rather than unusually colored.

Problems associated with Dy

Dysprosium can be very dangerous, for instance explosion hazard if it gets mixed with air and if there is source of ignition. The substance thin foil can be ignited by sparks or by static electricity. It is hard to put out the dysprosium fire by water. It produces flammable hydrogen gas if there is reaction with water. The dysprosium chloride fire can be put out with water, while on the other hand dysprosium fluoride and oxide are non flammable. The strong oxidizing agent is dysprosium nitrate and can be ingite fire if comes in contact with organic substances. The dysprosium can be toxic, when the dysprosium salt like dysprosium nitrate and chloride ingested. The non toxic salt is insoluble salts.

Safety Precautions

There are several precautions that could be taken in managing and handling the dysprosium. It is very air and moisture sensitive. It should be store in dry, tight and cool containers. Dysprosium is toxic and can be avoid breathing dusts or direct or long contact with skin and eyes. Like many other materials in powder form, it would be best to avoid creating dust of this product because it can create dust explosion. In the transfer process, use grounded/bonded equipment and non sparking tools. Wherever this material is stored; take precautions of not storing, using, or consuming beverages or any kind of food in that area. Before eating, drinking, use of tobacco or using toilet, wash your hands. There should be safety shower and eyewash fountain in the area where this product has been using. Oxygen should be available.

Current research

“Existing patterns in particle use or in structure consist of commercialization of technologies such as fast hardening and metal injection casting and production of heavy supplement metallurgy products.Dysprosium Particles are also available as Nanoparticles. Our standard Powder particle sizes average in the range of – 325 mesh, – 100 mesh, 10-50 microns and submicron (< 1 micron). We can also provide many materials in the nanoscale range” (Dysprosium, 2011). Dysprosium is also can be used in special kind ceramic arrangements mainly depending on BaTiO formulations. From the recent research we can find that dysprosium can be use in dysprosium iron garnet (DyIG), silicon can be implanted with dysprosium and holmium to create donor centers.

Dysprosium is one of the important elements that can help emerge clean energy technologies. Current research shows that Japan is the only country that has significant amount of dysprosium deposits, “with the new mines opening in Australia and Canada only containing small quantities of the element in their rare earth ores. Even the US DoE’s most conservative projections predict a shortfall of dysprosium before 2015” (Dysprosium, 2011).

Work Cited

Heiserman, D. L., (1992). Exploring Chemical Elements and their Compounds. TAB Books. Pp. 236-238. ISBN 0-8306-3018-X

Humphries, M., (2011), Rare Earth Elements: The Global Supply Chain. Retrieved from Congressional Research Service from http://www.fas.org/sgp/crs/natsec/R41347.pdf

Emsley, J., (2001), Nature’s building Blocks, Oxford: Oxford University Press. PP. 129-132. ISBN 0198503415.

“Dysprosium.” New Scientist 210.2817 (2011): 40. Academic Search Complete. Web. 3 May 2012.