A Geological Review survey estimates that Bayan Obo mining complex in Inner Mongolia region of China could yield 1 million tonnes of thorium.
About Thorium
- Thorium is a radioactive element that occurs naturally in low concentrations (about 10 parts per million) in the Earth’s crust.
- Source: Thorium is found in trace quantities in most rocks and soils and is more abundant than uranium.
- Most common source of thorium is the rare earth phosphate mineral, monazite, whose richest concentrations are found in placer deposits.
- Reserves: India has the largest thorium reserves in the world (11.93 million tonnes of Monazite, containing 1.07 million tonnes of thorium) and is followed by Brazil, Australia, and USA.
- Properties: It is a soft, ductile & silvery-white heavy metal in its pure form.
- Essentially all naturally occurring thorium is present as Thorium-232 (Th-232).
- Fuel for nuclear reactors: Thorium-232 itself is not fissile and is required to be converted into a fissile material Uranium-233 (U-233).
- It is done through irradiation of Th-232 using U-233 or Plutonium-239 (Pu-239) as fissile driver.
- Reactors able to use thorium: Heavy Water Reactors (PHWRs), Pressurized (Light) Water Reactors (PWRs), Fast Neutron Reactors (FNRs) etc.
