3. THORIUM
● Thorium is a naturally-occurring, slightly
radioactive metal.
● Discovered in 1828 by the Swedish chemist
Jons Jakob Berzelius.
● Named it after Thor, the Norse god of thunder.
● It is found in small amounts in most rocks and
soils.
● It is about three times more abundant than
uranium.
5. CHARACTERISTICS OF THORIUM
● Pure thorium is a silvery-white metal.
● The physical properties of thorium are greatly
influenced by the degree of contamination with the
oxide.
● Pure thorium is soft, very ductile, and can be cold-
rolled.
● Changes from F.C.C to B.C.C. at 1350 c
● Thorium metal is paramagnetic with a ground state of
6d27s2
6. THORIUM MINERALS
● The Mineral Thorogummite
Chemistry: (Th, U)2(SiO4)(2 - X)(OH)4X, Thorium
Uranium Silicate Hydroxide.
7. ● The Mineral Thorite
Chemistry: (Th, U)SiO4, Thorium Uranium
Silicate.
8. MINING AND CONCENTRATING
● Monazite beach sands are readily mined with conventional placer mining
equipment and procedures. The dredged monazite is admixed with a variety
of other minerals, including silica, magnetite, ilmenite, zircon, and garnet.
Concentration is accomplished by washing out lighter minerals in shaking
tables and passing the resulting monazite fraction through a series of
electromagnetic separators, which separate monazite from other minerals by
virtue of their different magnetic permeabilities
9. THORIUM AS A NUCLEAR FUEL
● Fertile Material
● Fissionable
● Most Abundant Nuclear Fuel
10. ● In the thorium cycle, fuel is formed when 232Th
captures a neutron (whether in a fast reactor or
thermal reactor) to become 233Th. This
normally emits an electron and an anti-
neutrino(ν) by β−decay to become 233Pa. This
then emits another electron and anti-neutrino by
a second β−decay to become 233U, the fuel:
11. ADVANTAGES
THORIUM: CLEANER NUCLEAR POWER?
Uranium-based reactors can be retrofitted, bringing major
benefits –
improving security
allaying environmental concerns
improving economics
The fuel cycle can also be proliferation resistant, stopping a
reactor from producing nuclear weapons-usable plutonium
With the spent fuel having significantly reduced volume,
weight and long-term radio-toxicity, safety margins are
increased and operating costs reduced.
12. DISADVANTAGES
Thorium mining produces waste products like mill tailings which can escape
into the environment and as with uranium, thorium mining produces
radioactive mining residues.
Besides being relatively costly to produce, the thorium can be difficult to
reprocess.
Thorium itself can be difficult to recycle because it is contaminated by highly
radioactive Th-228 and despite the lower overall radioactivity.
Owning and handling small amounts of thorium, such as a gas mantle, is
considered safe if care is taken not to ingest the thorium -- lungs and other
internal organs can be penetrated by alpha radiation.
Exposure to aerosolized thorium can lead to increased risk of cancers of the
lung, pancreas and blood. Exposure to thorium internally leads to increased
risk of liver diseases.