Brines occur naturally in many environments, and they are increasingly recognized as potential sources of valuable minerals. Underground aquifers can become saline as water slowly dissolves minerals from surrounding rock formations. In the simplest terms, brine refers to water containing a high concentration of dissolved salts. But beneath that straightforward definition lies a complex mixture. Along with sodium chloride, brine often carries a wide range of other dissolved minerals, some of which have significant economic value.
In recent years, attention has grown around the presence of critical minerals and medically important radioisotopes in subsurface brines. Lithium, radium, rare earth elements, bromine, iodine, magnesium, and other metals may occur in low concentrations but in volumes large enough to make recovery economically meaningful. As demand for strategic materials continues to rise, these fluids are increasingly being studied as potential sources for mineral extraction.
Produced Water in Oil and Gas Operations
One of the most significant industrial sources of brine is oil and gas production. Water naturally present in deep geological formations often emerges alongside hydrocarbons during extraction. This saline fluid, commonly referred to as produced water, can increase over the life of a well. As hydrocarbon output declines, water often flows into the reservoir more readily, meaning older wells may produce far more brine than oil or gas [1].
Historically, the petroleum industry has treated this saline water primarily as a waste stream. The most common disposal method is reinjection, in which the brine is pumped back underground into deep disposal wells [2]. While this approach manages large volumes of saline water, it also represents the loss of potentially valuable dissolved materials.
Critical Minerals Hidden in Brine
Produced brine can contain more than just salts. Depending on the geology of the reservoir, it may also contain dissolved elements of economic value, including lithium, radium, rare earth elements, bromine, iodine, and magnesium. Some of these materials are critical to modern manufacturing, particularly in batteries, electronics, and energy storage systems. As global demand for such materials rises, researchers and energy companies alike are examining whether produced water from oil and gas wells could become a secondary source of income rather than a liability.
One area receiving particularly strong attention is lithium recovery from oilfield brines. Lithium is a critical component in rechargeable batteries used in electric vehicles, grid-scale energy storage, and consumer electronics. Traditionally, most lithium production has come from hard-rock mining or from large evaporative salt flats. However, interest is rapidly growing in recovering lithium from brine produced during oil and gas operations. Many subsurface formations contain trace levels of lithium that accumulate in formation waters over geologic time. Although these concentrations are typically lower than those found in dedicated lithium brine deposits, the sheer volume of produced water generated by oil and gas fields can make recovery economically attractive.
Challenges of Extracting Metals from Dilute Brines
As global demand for critical minerals continues to rise, unconventional sources are becoming increasingly important. Brines associated with oil and gas production represent one such opportunity. These fluids are already being produced in large volumes and handled through existing infrastructure, yet the valuable elements they contain are often overlooked or difficult to extract.
Lithium extraction, for example, is complicated by the many similar elements that are also found in brines. For the lithium extraction process to be economical, high selectivity for lithium is required. Direct lithium extraction (DLE) technologies are not highly selective for lithium in the presence of competing ions such as sodium, potassium, calcium, magnesium, and iron. Thus, extensive pre- and post-processing steps are needed, in addition to DLE processes, to purify the lithium and produce battery-grade lithium end-products.
Molecular Recognition Technology™ for Selective Recovery
Molecular Recognition Technology™ (MRT™) developed by IBC Advanced Technologies offers highly selective, cost-efficient recovery of the valuable metals found in brines. MRT™ SuperLig® resins are designed with highly selective ligands that recognize and bind specific metal ions, allowing valuable elements to be separated even in highly saline and chemically complex solutions.
The power of MRT™ to quickly and simply recover critical minerals from brines is especially evident when it comes to lithium extraction. Unlike direct lithium extraction (DLE) technologies, IBC’s Direct Lithium to Product® (DLP™) process does not require additional pre- or post-processing steps to purify lithium. The lithium is extracted and purified with highly selective MRT™ SuperLig® resin before being transformed directly to battery-grade lithium hydroxide monohydrate or lithium carbonate product.
This modular DLP™ process is free of carbon emissions and operates at ambient temperature and atmospheric pressure so very little energy is consumed. Water and reagents are recycled to minimize waste, costs, and environmental impact. DLP™ is “water-neutral” (returning Li-depleted brine to the source). By increasing extraction efficiency and decreasing processing steps, the DLP™ process makes lithium production efficient, economical and environmentally friendly.
When integrated with oil and gas, geothermal, or other subsurface fluid operations, MRT™ can help transform produced water from a disposal challenge into a potential resource stream. Recovering critical minerals from brines not only diversifies supply but also creates new opportunities for value generation from existing energy infrastructure.
As interest in energy transition materials, medical radioisotopes, and strategic metals continues to grow, the role of brines in global mineral supply chains is likely to expand. Technologies capable of selectively recovering these materials will play an important role in determining how effectively this resource can be utilized.
Sources
[1]. EPA. TENORM: Oil and Gas Production Wastes. February 19 2026 https://www.epa.gov/radiation/tenorm-oil-and-gas-production-wastes#:~:text=How%20are%20drilling%20wastes%20produced,inside%20pipes%20and%20drilling%20equipment.
[2] Paul F. Hudak, David J. Wachal. Effects of brine injection wells, dry holes, and plugged oil/gas wells on chloride, bromide, and barium concentrations in the Gulf Coast Aquifer, southeast Texas, USA. Environment International, Volume 26, Issues 7–8. 2001.https://www.sciencedirect.com/science/article/pii/S0160412001000332#aep-section-id15