Periodic Table -> Palladium

Palladium


Palladium Details

Palladium Symbol: Pd

Palladium Atomic Number: 46

Palladium Atomic Weight: 106.4

What is Palladium?

Palladium (atomic number 46, chemical symbol Pd) is a ductile and soft metal with a lustrous sheen. Other elements in the platinum group include osmium, iridium, and palladium. It is an element of low toxicity and is resistant to corrosion.

The metal was discovered in 1803 by the English physicist and chemist William Wollaston. Today, it is found in South and North America, Ethiopia, Russia, Brazil, and Australia. Palladium is also found in copper and nickel deposits on the territory of South Africa and Canada. Most of the palladium is in the form of byproduct from nickel refining.

Palladium has the lowest density and lowest melting point of all PGMs. The element resembles platinum in color and softness. It is ductile and soft when subjected to heat treatment, but its strength increases when cold-worked. Palladium reacts with and dissolves slowly in hydrochloric, nitric, and sulfuric acid. It does not tarnish at normal temperatures but tarnishes in moist environments that contain sulfur. The element is attacked by both sulfuric acid and nitric acid.

The metal is found in nickel-copper deposits and with other elements from the platinum group metals. It is mainly a byproduct from nickel refining, but some minerals have been found to be rich in palladium. The metal is extracted from nickel and copper deposits and deposits of other platinum group metals. These are found in South and North America, Ethiopia, Russia, Brazil, and Australia. The copper and nickel deposits are mainly in South Africa and Canada.

Palladium has valance of 2, 3, or 4. Its boiling point is 2970 C and its melting point 1554 C. Extraction is a complex process because palladium is mixed with platinum and other metals in ores. In some cases, the main focus of operations is the extraction of palladium or platinum, but it may be a byproduct. The base metal byproduct or ore is treated with a mixture of nitric acid and hydrochloric acid, known as aqua regia. A solution that contains H2PdCl4, platinum, and gold is formed.


Palladium is used to manufacture watches, electrical contacts, and surgical instruments. The element is also used in photography and technology. Ceramic capacitors, watch springs, and connector platings are also made using palladium. The element forms palladium hydroxide at room temperature and absorbs hydrogen. Thus it is used for hydrogen storage. Moreover, palladium has a higher absorption capacity than other transition metals and high x values should be reached before it loses ductility.

The metal is also used as an alloying agent and in different dehydrogenation and hydrogenation processes as it acts as a catalyst. Palladium compounds are used as catalysts for carbon-carbon bond forming. Primary alcohols are oxidized in alkaline media by using palladium as an electrocatalyst. In addition, carbon monoxide detectors use palladium dichloride which absorbs carbon monoxide.

Exposure may cause vomiting, skin sensitivity, and irritation of the respiratory tract and the eyes. While palladium has a low toxicity, its compounds are considered carcinogenic and very toxic. Palladium chloride has been shown to cause kidney, liver, and bone marrow damage in laboratory conditions. The compound is dangerous and toxic when absorbed through skin, inhaled, or ingested. Most plant species tolerate low levels of palladium, but some are killed by it. The growth rate of plants may be affected above certain level.



You can link to this page, using the code below:



Periodic Table | Banks


© ElementsDatabase.com 2015 | Privacy | About | Contact