A game-changing award-wining NETL technology that can effectively capture heavy metals from acid mine drainage and municipal water supplies and extract beneficial critical minerals such as aluminum, nickel and rare earth elements (REE) from water, has been granted a U.S. patent, bringing it step closer to wide use throughout the nation.

The patent for Multi-functional Basic Immobilized Amine Sorbents for Removal of Metal Contaminants from Wastewater was issued as U.S. patent number 11,850,571 B2 in December 2023. The technology is known as multi-functional sorbent technology (MUST).

According to the Environmental Protection Agency, “Sorbents are insoluble materials or mixtures of materials used to recover liquids through the mechanism of absorption, or adsorption, or both. Absorbents are materials that pick up and retain liquid distributed throughout its molecular structure causing the solid to swell (50% or more).”

MUST, initially developed for use in carbon capture applications, won a 2021 R&D 100 Award, known as the “Oscar of Innovation,” and a bronze medal in the eco-innovation category of the Edison Awards in 2022.

After working on carbon capture applications, NETL developers McMahan L. Gray, Fan Shi, Walter C. Wilfong, Qiuming Wang, and Brian W. Kail discovered that MUST can play a significant role in removing toxic metals that flow from thousands of abandoned and active mines across the nation that pollute streams, destroy aquatic life and contaminate water supplies.

Additional opportunities for even wider use of the technology soon became apparent. For example, MUST can be used to remove lead from municipal drinking water and radioactive species from nuclear wastewater. MUST can also extract beneficial critical minerals from water.

REEs and other critical minerals are used in the production of medical equipment, clean energy components, electric vehicles, electronics, military technology and a wide variety of other consumer goods.

“Working with a previous commercial partner and building upon our own internal research, we effectively demonstrated that MUST can remove metals from acid mine drainage,” Gray explained. “But that was only the beginning. This patent will help us attract new partners to work with NETL to adapt the technology for use in other critical metal recovery and water treatment applications and that will lead to cleaner water for millions of people and a reliable supply of REEs for hundreds of consumer products and national defense.”

MUST is a suite of versatile and low-cost, regenerable sorbent materials that look like fine grains of sand. MUST strongly binds and removes selenium, lead, cadmium, chromium, arsenic, mercury and other heavy metals from acid mine drainage and other industrial effluents.

Because MUST is a particle sorbent with open pores, rapid transport of metals into and out of the sorbent provides quick adsorption-desorption cycling. NETL research has demonstrated that the adsorption capacity of MUST for some key metal contaminants is 50% higher than other commercial exchange methods.

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 using 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.