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| Atomic Number: | 44 | Atomic Symbol: | Ru | | Atomic Weight: | 101.07 | Electron Configuration: | 2-8-18-15-1 | | Shells: | 2,8,18,15,1 | Filling Orbital: | 4d7 | | Melting Point: | 2250oC | Boiling Point: | 3900oC | | Description: | Rare hard brittle silvery metal | | Uses: | Used for eye treatment; also used to harden platinum and
palladium. Aircraft magnetos use platinum alloy with 10% ruthenium |
History(L. Ruthenia, Russia). Berzelius and Osann in 1827 examined the
residues left after dissolving crude platinum from the Ural mountains in aqua
regia. While Berzelius found no unusual metals, Osann thought he found three new
metals, one of which he named ruthenium. In 1844 Klaus, generally recognized as
the discoverer, showed that Osann's ruthenium oxide was very impure and that it
contained a new metal. Klaus obtained 6 g of ruthenium from the portion of crude
platinum that is insoluble in aqua regia.
SourcesA member of the platinum group, ruthenium occurs native with
other members of the group in ores found in the Ural mountains and in North and
South America. It is also found along with other platinum metals in small but
commercial quantities in pentlandite of the Sudbury, Ontario, nickel-mining
region, and in pyroxinite deposits of South Africa. The metal is isolated
commercially by a complex chemical process, the final stage of which is the
hydrogen reduction of ammonium ruthenium chloride, which yields a powder. The
powder is consolidated by powder metallurgy techniques or by argon-arc wleding.
Properties- Ruthenium is a hard, white metal and has four crystal modifications.
- It does not tarnish at room temperatures, but oxidizes explosively.
- It is attacked by halogens, hydroxides, etc.
- Ruthenium can be plated by electrodeposition or by thermal decomposition
methods.
Uses- The metal is one of the most effective hardeners for platinum and palladium,
and is alloyed with these metals to make electrical contacts for severe wear
resistance.
- A ruthenium-molybdenum alloy is said to be superconductive at 10.6 K.
- The corrosion resistance of titanium is improved a hundredfold by addition
of 0.1% ruthenium.
- It is a versatile catalyst.
- Hydrogen sulfide can be split catalytically by light using an aqueous
supsension of CdS particles loaded with rughenium dioxide.
- It is thought this may have application to removal of H2S from oil refining
and other industrial processes.
- Compounds in at least eight oxidation states have been found, but of these,
the +2, +3, and +4 states are the most common.
HandlingRuthenium tetroxide, like osmium tetroxide, is highly toxic. In
addition, it may explode.
Ruthenium compounds show a marked resemblance to
those of cadmium.
CostThe metal is priced at about $30/g.
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