A portable and economic process for quickly extracting lithium from natural brines and produced water from oil and gas extraction has been developed by the U.S. Department of Energy’s NETL and is attracting commercialization attention from private industry as the world transitions to electric vehicles and develops renewable energy generators that store surplus electricity in batteries for future use.

Natural brines consist of water that is found underground, in salt lakes, or as seawater. In addition to lithium, natural brines exhibit significant concentrations of valuable minerals like rare earth elements (REEs) and critical metals.

Produced water results when oil or gas is extracted from rocks that contain water. It also results from hydraulic fracturing when fracturing fluid returns to the surface. Produced water is a byproduct of most oil and gas extraction and can also be a source for lithium and REEs.

Lithium is a naturally occurring metal. It makes up a mere 0.0007 percent of the Earth's crust, according to the Jefferson Lab, and it's only found locked up in minerals and salts. Since the early 1990s, lithium has been used increasingly in batteries for rechargeable power for laptops, phones and other digital devices as well as for new electric vehicles. The U.S. has one lithium mine in Nevada. Chile and Australia produce the most lithium in the world. The gap between lithium demand and supply is expected to widen.

REEs are crucial for a variety of economic, energy and defense applications. The current supply chain is dominated by other countries. A domestic source would insulate the U.S. from disruptions in global trade of REEs.

The patented NETL invention (United States Patent: 10315926 (uspto.gov) and United States Patent Application: 0210047196 (uspto.gov)) is currently being evaluated by One World Lithium Inc., for use on naturally occurring brines with the exception of sea water and geothermal brines, through a non-exclusive research and evaluation license.

Other invention applications with licensing opportunities include: brines produced as a co-product, by-product, or waste stream from industrial practices or energy production/development such as geothermal power plants, oil & gas production, carbon sequestration, enhanced oil recovery, and coal bed methane recovery; and brines produced in association with abandoned mine land.

Jinichiro Nakano, one of the NETL co-inventors of the new process, explained that current lithium recovery technologies that use diesel-intensive evaporation ponds can take one or two years to generate lithium from natural brines. Those technologies also require substantial amounts of freshwater, solid chemicals and acids that have imposed environmental burdens. Some state-of-the-art methods can reduce the time it takes to harvest the elements at the expense of freshwater, chemicals and/or acids, but still require traditional mineralization steps that generate significant quantities of carbon dioxide (CO2).

“The technology advanced by NETL uses a unique CO2 injection technique to produce lithium carbonate ‘directly’ in a brine,” he said. “The technology is the next generation of direct lithium extraction process that does not require adsorbents, absorbents, and membranes. It eliminates the need for freshwater, solid chemicals, acids, and a mineralization facility to produce lithium minerals. CO2 may be mixed into a brine in such a way that mineralization of a brine occurs almost instantly even under ambient conditions. This make possible accelerated recovery of critical materials from brines with a relatively small footprint and in an environmentally benign fashion.”

NETL co-inventor Anna Nakano added that the new process has a range of advantages.

“The CO2 used in the process is readily available in the air,” she said. “It can also be sourced from industrial waste streams. Because it is portable enough to facilitate full operation at the source of brine, it eliminates the hundreds of millions of dollars for capital investment that would otherwise be required in current processes.”

Nakano said the innovation represents a way to build sustainable domestic supply chains for lithium and REEs.

“In addition to natural brines and produced water, the process could extract lithium, REEs and other critical materials from sea water,” he said. “It can be used as a tool for carbon sequestration and to clean contaminated water.”

NETL is a U.S. Department of Energy national laboratory that drives innovation and delivers technological solutions for an environmentally sustainable and prosperous energy future. By leveraging its world-class talent and research facilities, NETL is ensuring affordable, abundant and reliable energy that drives a robust economy and national security, while developing technologies to manage carbon across the full life cycle, enabling environmental sustainability for all Americans.