Thorium is a naturally occurring silvery white metal that is more common in the Earth's crust than other metals like tin, mercury, and silver. It was discovered in 1828 by Swedish chemist Jöns Jacob Berzelius and named after the Norse god Thor. Thorium-232 is the most common isotope of thorium and has a half-life of 14 billion years. While thorium has been used in some applications, nuclear experts have become more interested in it as a potential energy source because thorium reactors could produce much more energy per ton than uranium reactors and produce less nuclear waste.

1. Thorium
By Johanna Becker

2. What is it?
Thorium is one of the heavier elements
in the period table with the atomic
number of 90.
Jöns Jacob Berzelius was the Swedish
Chemist who discovered Thorium in
1828 (alongside Selenium and
Silicon) and named it after Thor, the
Norse god of thunder.
It is more common in the Earth’s crust
than tin, mercury and silver, and
three times more abundant than
naturally occurring uranium, which
form the basis for most nuclear fuels.
(1)
(2)
(D)

3. Properties
Pure thorium is a naturally occurring silvery white metal.
It has a melting point of 2023.15 K (1750oC).
It is a solid at room temperature.
It dissolves slowly in water.
Thorium-232 (The most commonly occurring isotope of thorium) has a half life of 14
billion years.
(A)

4. (3)

5. What is it used for?
Since 2008, Nuclear experts have become more interested in Thorium because
they believe that Thorium will be more energy efficient than Uranium.
Carlo Rubbia, a Nobel Prize-winning physicist at the European Organisation
for Nuclear Research, estimates that “one ton of Thorium can produce as
much energy as 200 tons of Uranium or 3.5 million tons of coal.
The thorium deposits that have already been identified would meet the entire
world’s energy needs for at least 10,000 years.”
(B)
(C)

6. Do we have the technology?
We do have the technology to use thorium efficiently due to the prototype
reactors built in the 60s.
One of them ran for four years until it closed down in 1969.
Until the term of this century, only India - which has a limited uranium supply
- kept a serious thorium research programme.

7. Advantages
• Doesn’t have to be enriched before it gets burned.
• No enriched by-products (e.g. Plutonium) which can be used to make
weapons.
• Higher melting point than Uranium.
• Less nuclear waste.
Disadvantages?
• ?

8. Comparison
(4)

10. Bibliography
Images:
 http://thoriumforum.com/sites/default/files/styles/large/public/thorium-crystal.jpg?itok=EyPNNdwr
[10/18/2012 - 21:46] (1)
 http://www.larrymylesreports.com/images/thorium_metal_ingot.jpg [April 2011] - (2)
 http://www.flickr.com/photos/68816401@N00/5233682037 [5/12/2010] - (3)
 http://www.extremetech.com/extreme/143437-uranium-killed-the-thorium-star-but-now-its-time-for-round-two
[12/18/2012] - (4)
Information:
 http://www.epa.gov/radiation/radionuclides/thorium.html#use [3/6/2012] – (A)
 http://en.wikipedia.org/wiki/Thorium-based_nuclear_power [18/2/2014] – (B)
 http://prospect.org/article/will-thorium-save-us-all [?/?/2014] - (C)
 “The Week” magazine issue – article “The Metal that could save the World” [1/2/2014] (D)