Minnesota teen engineers corn stalks to concentrate lithium from weak brines
High-school student John Liu turned corn stalk pith and wheat straw into a passive system that concentrates lithium from dilute brines, earning top honors at state and international science fairs.
John Liu, a high-schooler from St. Paul, devised a method that uses corn stalk pith and wheat straw, treated to enhance liquid transport, to pre-concentrate lithium from low-grade brines through capillary flow and evaporation. The approach links two challenges: the growing demand for lithium and the abundance of agricultural residues. Liu’s work earned a Gold Award at the 2026 Minnesota State Science and Engineering Fair, ranking in the top five percent of entries.
He was subsequently named a Minnesota finalist for the Regeneron International Science and Engineering Fair, where he achieved second place in the environmental engineering category and received $2,400. The Minnesota Academy of Science also noted his receipt of the Chief of Naval Research Scholarship. This achievement highlights a sustainable, low-cost avenue for lithium recovery that could benefit battery production and waste management.
Why it matters
It shows how cheap farm waste could help meet rising lithium demand for batteries.
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