Rare Metals and Rare-Earth Elements in Deep-Ocean Mineral ...
Rare Metals
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Transcript of Rare Metals
Rare Earth Metals nature’s little ways of helping us in our daily lives
Definition of “Rare Earth Metal”
Definition of Rare Earth metals● Name alludes to their elusive nature as they rarely exist
in their pure form● Collection of 17 chemical elements in the periodic table
(15 lanthanides, Scandium and Yttrium)● Scandium and Yttrium are considered rare earth
elements as they tend to occur in the same ore deposits as the lanthanides and exhibit similar chemical properties
Rare Earth Metal #1 - scandium - A silvery metal that tarnishes in air, burns easily and reacts with water- Mainly used for research purposes- Scandium Iodide is added to mercury vapour lamps to produce a highly efficient light source resembling sunlight, which is important for indoor lighting and night-time colour television screens- Also used as a tracing agent in refinery crackers for crude- Has a great potential as its’ density is almost as low as aluminium, but has a much higher melting point, thus attracting the interest of spacecraft designers.
Rare Earth Metal #2 - Gadolinium● Gadolinium is a bright, soft, silvery-white metal that is both ductile and
malleable.
USES: ● Gadolinium is used in alloys of iron and chromium to improve resistance
to high temperatures and oxidation.● Gadolinium is used to make gadolinium yttrium garnets which have
microwave applications.● Gadolinium compounds are used as green phosphors in color television
picture tubes.
Rare Earth Metal #3 - Ytterbium ● Bright, soft, silvery-white metal that is both ductile and malleable● Tarnishes quickly in air● Reacts slowly with water● Dissolves rapidly in mineral acids● Extracted from mineral monazite by different extraction methods such as ion
exchange and solvent extraction
Uses of Ytterbium● Radioactive isotope of ytterbium is used in portable x-ray machines that need no
electricity● Used in stress gauges to monitor ground deformations caused by earthquakes or
underground explosions → Ytterbium’s electrical resistance increases by order of magnitude under very high physical stress
● Used in alloys and added to stainless steel to improve grain refinement and strength
Rare earth metal #4 -Neodymium❖ Neodymium is a silvery-white metal. ❖ It is one of the more reactive earth metals and tarnishes in air,
forming an oxide layer that falls off and exposes more metal to oxidation. -stored in light mineral oil or sealed in plastic
1. Used with iron and boron to create powerful permanent magnets (NIB magnets). -used in motors, computer disk drives, handphones, cell phones and wind turbines.
-->plays an essential role in the miniaturisation of gadgets (before, producing strong magnetic fields for motors required big and heavy magnets)2. Used as a colourant for glasses and enamels3. Used as a crystal in ND:YAG lasers- to treat skin cancers, for laser
hair removals and to cut and weld steels.
Referenceshttp://www.periodni.com/rare_earth_elements.htmlhttp://www.chemicool.com/elements/gadolinium.htmhttp://www.rsc.org/periodic-table/element/70/ytterbiumhttp://www.chemicool.com/elements/ytterbium.htmlhttp://education.jlab.org/itselemental/ele070.htmlhttp://www.popularmechanics.com/technology/engineering/news/important-rare-earth-elements#slide-4http://www.azom.com/article.aspx?ArticleID=1595#_Key_Propertieshttp://www.chemicool.com/elements/neodymium.html