Palladium is a chemical element with the chemical symbol Pd and an atomic number of
46. It is a rare and lustrous silvery-white metal discovered in 1803 by William Hyde Wollaston. He named it after
the asteroid Pallas, which was
itself named after the epithet of the Greek goddess Athena, acquired by her
when she slew Pallas. Palladium,platinum, rhodium, ruthenium, iridium and osmium form a group of elements referred to
as the platinum group metals (PGMs). These have similar
chemical properties, but palladium has the lowest melting point and is the
least dense of them.
Over half
of the supply of palladium and its congener platinum
goes into catalytic converters, which convert up to
90% of harmful gases from auto exhaust (hydrocarbons,carbon monoxide,
and nitrogen dioxide)
into less-harmful substances (nitrogen, carbon dioxide and water vapor).
Palladium is also used in electronics, dentistry, medicine, hydrogen
purification, chemical applications, groundwater treatment and jewelry.
Palladium plays a key role in the technology used for fuel cells,
which combine hydrogen and oxygen to produce electricity, heat, and water.
Ore deposits of palladium and other PGMs are rare,
and the most extensive deposits have been found in the norite belt of the Bushveld Igneous Complex covering theTransvaal Basin in South Africa, the Stillwater Complex in Montana, United States, theThunder Bay District of Ontario, Canada, and the Norilsk Complex in Russia. Recyclingis also a source
of palladium, mostly from scrapped catalytic converters. The numerous
applications and limited supply sources of palladium result in the metal
attracting considerable investment interest.
