Mineral magnesite could help remove CO2 from the atmosphere

Researchers found a rapid way of producing magnesite, a mineral that stores carbon dioxide. If developed to an industrial scale, it could help with long-term CO2 storage.

The greenhouse gas carbon dioxide is one of the culprits causing global warming. There are technologies available that sequester CO2, but these have both practical and economic limits.

Magnesite (MgCO3) is a naturally-occurring mineral, found as veins in magnesium rich rocks like ultramafic rocks. The mineral is used in large quantities to produce magnesium oxide, which is used to line furnaces and kilns, but magnesite is also used in jewellery. A tonne of magnesite can remove around half a tonne of CO2 from the atmosphere, but the rate of formation is very slow.

The research is two-fold. Firstly, the researchers found how and how fast magnesite forms naturally, a process that takes hundreds to thousands of years. Secondly, they found a way to speed up the process dramatically.

The process involves polystyrene microspheres, which are used as a catalyst. Without the need for high temperatures, magnesite crystals started to form within 72 days. For now, the process is experimental, but if the researchers are able to scale the process up to industrial size, the mineral would become a viable option in storing CO2, or even directly removing carbon dioxide from the air.

Photos: Ian Power / Rob Lavinsky / ShiluGeo1PU