Rare Earth Metals Extraction From The Sea Floor Gets Easier

Economists and geologists warned that the world may deplete essential earth metals needed for manufacturing various substances. Demand exceeds supply; consequently, prices could increase. This outcome may raise extraction costs for remaining rare metals. A group of geochemists discovered a method to recover these metals from below the sea.

The scientists published a report in the Journal of Applied Geochemistry. They report that rare earth elements can be extracted from solid ferromanganese nodules dispersed over the deep seabed. The nodules are known as ferromanganese deposits. They form when liquid iron and manganese are deposited on seabed sediments from seawater.

The geochemists developed a solvent named Desferrioxamin-B to serve as a key component of the extraction method. This solvent adheres more strongly to certain metals than to others. Consequently, when applied to the ferromanganese nodules, it extracts the rare earth elements effectively while leaving other metals in the nodules. The researchers claim that this method extracted approximately 80% of four rare earth elements from the ferromanganese nodules after refining their ore leaching process.

The findings are anticipated to motivate mining companies to secure licences for seabed exploration and extraction. They search for materials essential for portable electronic devices and hybrid vehicle batteries. The United Nations International Seabed Authority granted 30 exploration licences since 2001 for the mid-Atlantic, Pacific and Indian Oceans. The Authority observed an increase in applications from exploration companies and is planning to issue about seven additional licences.

The United Nations did not remain inactive. In 2013, the United Nations published an update outlining its plan for a legal framework for extraction activities. Consequently, private companies were granted access to licences for extracting oil, gas and minerals from 2016. Rare metals are distributed throughout the Earth's crust. They are not available in deposits in sufficient quantities. This suggests that these metals may not be as scarce if an alternative extraction process is developed.