LiFT: Lithium for Future Technology
Identifying sustainable lithium resources for a low carbon economy
We are investigating geological resources that have the potential to produce lithium, including Li-clays in the USA and Turkey, Li-rich borates in Serbia and Li-micas in granites and pegmatites across Eurasia, Africa and Australia.
How do lithium deposits form?
Major lithium deposits are largely formed in parts of the world where plate tectonics have led to continental collision.
We will test the hypothesis that within these collisional environments there is a 'life-cycle' of tectonic processes that is reflected in the formation of different types of lithium deposits.
Lithium is moderately concentrated in igneous rocks that are formed in this setting. Lithium is a relatively soluble element that is readily leached and weathered from these rocks (particularly by hot geothermal water) and the lithium-rich waters may accumulate in basins that are also formed during continental collision.
If the climate is arid, the waters evaporate to form a lithium-rich brine that can be an economically viable lithium deposit in its own right. In these brine basins, complex chemical processes and extreme microbial life may play a role in cycling elements and concentrating the lithium into sediments.
Over time, the geothermal and volcanic activity ceases and the lithium-rich sediments may be buried and thus preserved for millions of years. Subsequently, these buried rocks may also serve as a source of lithium that can be extracted. With further burial and then heating, these lithium-rich sediments can reach temperatures at which they undergo melting and the formation of lithium-enriched pegmatites and granites.
At each stage of the lithium life cycle there are uncertainties regarding the source of lithium and how it is transported and trapped.
The different types of lithium deposits also vary in how easy it is to extract the lithium, and we need to consider how to do this in an environmentally responsible way.
We will tackle these problems by bringing together a group of scientists who have considerable expertise in all aspects of this lithium journey.
We will use a wide range of techniques, from simple geological observations through to highly sophisticated isotopic analyses and microbiological techniques, to track the behaviour of lithium.
We will work alongside industry partners to identify the types of deposits that can be profitably extracted while simultaneously minimising any damage to the environment, and we will investigate the potential for more sustainable methods of lithium extraction using microbial processes.
The Natural History Museum are co-leading two of the work packages focused on how lithium behaves in geological systems associated with volcanoes, sedimentary basins and more complex geological systems.
These two packages complement other packages investigating lithium salar brines like the ones in the Andes of South America and other packages looking at global resources and a more sustainable lithium supply chain. The Natural History Museum will apply its advance mineralogical expertise supported by its state-of-the-art analytical facilities to the science questions. One of our latest instruments includes a new TESCAN TIMA automated analytical scanning electron microscope, recently purchased using a successful NERC capital grant.
The Museum researchers will be addressing the following scientific questions:
- How does lithium become enriched in the volcanic rocks and basins formed near to late-stage volcanoes in arc systems?
- Which minerals does lithium becomes incorporated into that may become potential economic sources for the metal in such basins?
- How did the giant Jadar lithium-boron deposit in Serbia form that is hosted in a Miocene-age volcano-sedimentary basin? The deposit, discovered by Rio Tinto in 2004, contains huge amounts of the unique new mineral jadarite, first characterised by Natural History Museum scientists.
- How does lithium become enriched around granites and pegmatites and are these rocks always related?
The Natural History Museum leads the regional lithium assessment based on field sampling of most prospective sites and their mineral characterization.
Developing a new quantitative understanding of the processes that link magmatic and sedimentary deposits, and brines, to aid in the search for new, sustainable lithium resources, together with innovative assessment of environmental impacts.
Total value of grant: £2.5 million with £307,000 for science at the Natural History Museum.