MAE Professor's Paper Predicts Nanoscale Means of Recovering Critical Minerals
Department of Mechanical and Aerospace Engineering (MAE) Professor and Associate Chair Jerry Shan has co-authored a recently published Nature Nanotechnology paper that discusses, according to Shan, "new boron-nitrite-nanotube membranes (BNNT) that can both recover critical materials such as lithium, as well as generate electricity from the concentration difference between salt and fresh water."
The paper is the result of collaborative research begun nearly a decade ago, with Shan and Sangil Kim, an associate professor of chemical engineering at the University of Illinois Chicago (UI), serving as lead principal investigators on an NSF-funded project. It was co-authored by both PIs, MAE professor Liping Liu, an undergraduate, and several former PhD students, including Semih Cetindag, credited as its first author.
Equally important is that the new artificial membranes also show promise for lithium separation.
According to Shan, the team's research offers two significant takeaways. First, a new physical mechanism is allowing ultrafast, lithium-selection transport in BNNTs. Second, the researchers have developed a new, scalable manufacturing technique for fabricating BNNT membranes.
The paper asserts that up until now, synthetic membranes have been less efficient than biological channels in transporting ions across cell membranes. The newly designed dense array of BNNTs has both displayed a conductance of lithium ions that is more than 30 times faster than expected, as well as an unexpected preference for transporting lithium over other alkali metals.
This unexpected selectivity not only challenges established paradigms of electrokinetic transport but also opens new avenues for selective ion separation in energy applications," the paper's co-authors maintain.
Shan foresees a future where power plants could be built at coastal estuaries to use fresh and saltwater to generate electricity. "Alternatively, they could be built to use brine from desalination plants and gray water," he suggests.
While using the new BNNT membranes to create sustainable "blue" energy is still a way off, Shan says that "we think that we've taken a major step toward making it scalable and economically viable. And we think that with continued work, there is potential for energy generation and resource recovery."
Rutgers and UIC have recognized the commercial potential of the team's work through a jointly held patent.
