PFAS waste turned into battery-grade lithium

March 10, 2026

In environmental chemistry, certain pollutants are so stubborn they earn the label “forever chemicals.”

Among the most infamous are perfluoroalkyl and polyfluoroalkyl substances (PFAS). These synthetic compounds accumulate in soil, infiltrate groundwater, contaminate drinking supplies, and resist natural degradation for decades. Their persistence has made PFAS a global environmental and public health concern.

Now, researchers at Rice University, led by chemist James Tour and scientist Yi Cheng, have developed an innovative solution that transforms PFAS waste into a valuable resource. Their breakthrough method converts toxic PFAS residues into a tool for sustainable lithium extraction — a critical component of the clean energy transition.

Turning PFAS waste into lithium resources

The team’s newly published research outlines a waste-to-value process that uses PFAS-contaminated materials to recover lithium from high-salinity brine. Instead of viewing PFAS as an environmental liability, the scientists reimagined them as a fluorine source capable of supporting lithium recovery.

“While lithium extraction from brine is often less environmentally harmful than traditional mining, challenges remain in selectivity, cost efficiency, and water consumption,” Cheng explained. “We recognized an opportunity to unlock the fluorine stored in PFAS and use it to recover lithium through a faster, lower-impact process.”

This approach addresses two pressing issues at once: eliminating hazardous PFAS waste and improving sustainable lithium production for battery manufacturing.

How the lithium extraction process works

The process begins with spent activated carbon — a filtration material commonly used to remove PFAS from firefighting foam and contaminated water. Once saturated, this carbon is typically classified as hazardous waste.

Rather than disposing of it, the Rice researchers identified it as a valuable fluorine reservoir.

When PFAS-laden activated carbon is combined with high-salinity brine, a controlled reaction environment forms. Within this mixture, fluorine anions trapped inside PFAS molecules are released and bind with lithium cations present in the brine. The result is lithium fluoride — a key compound used in lithium-ion battery electrolytes.

Cheng described the chemistry behind the process: lithium exists in brine as a positively charged ion, while fluorine remains locked within the negatively charged PFAS molecules embedded in the carbon. The goal was to liberate both ions and recombine them into lithium fluoride (LiF), which can then be collected and purified.

Flash Joule Heating: breaking the strongest bonds

To release fluorine from PFAS, the team used Flash Joule Heating (FJH) — a rapid, high-energy pulse technique that instantly raises temperatures above 1,000°C (1,832°F) within milliseconds.

These extreme conditions break the exceptionally strong carbon–fluorine bonds that make PFAS so environmentally persistent. Once freed, fluorine atoms quickly bond with lithium ions in the brine, forming lithium fluoride.

This step effectively destroys the “forever chemicals” while simultaneously creating a valuable lithium compound.

High-purity lithium recovery through rapid distillation

Extracting lithium from brine presents another challenge: the solution also contains competing elements such as magnesium, calcium, and potassium.

To isolate lithium fluoride, the researchers applied a second controlled heating stage between 1,676°C (3,048°F) and 2,260°C (4,100°F). At this temperature window, lithium fluoride vaporizes while heavier impurities remain solid.

This rapid flash distillation process produced lithium fluoride with 99% purity and achieved an 82% recovery rate — all within seconds.

Real-world battery performance

To validate the quality of the recovered material, the team incorporated the recycled lithium fluoride into standard lithium-ion battery electrolytes.

Extensive testing demonstrated that batteries using the recovered lithium exhibited enhanced stability and performance compared with conventional lithium sources. This confirms that PFAS-derived lithium can meet battery-grade standards for advanced energy storage systems.

A sustainable alternative to conventional lithium mining

Traditional lithium extraction from brine often relies on vast evaporation ponds that sit under the sun for months. These operations consume enormous volumes of water — frequently in arid regions already facing water scarcity — and can significantly disrupt local ecosystems.

In contrast, the Rice University process completes lithium recovery in minutes rather than months. It also reduces water usage and energy consumption compared with conventional brine mining methods.

A double environmental breakthrough

This innovative technology delivers a dual environmental benefit:

• It permanently destroys hazardous PFAS “forever chemicals.”

• It generates high-purity, battery-grade lithium for clean energy applications.

By converting one waste stream into a solution for another resource challenge, this method represents a major advancement in sustainable chemistry, lithium extraction technology, and environmental remediation.