New sun-powered device extracts lithium while desalinating seawater

Researchers at Zhejiang University in China have developed a novel solar-powered seesaw extractor (SPSE) designed to efficiently extract lithium from seawater while simultaneously desalinating it. This innovation addresses the growing global demand for lithium, a critical element for batteries in smartphones and electric vehicles, amid the environmental challenges posed by traditional land-based lithium mining. The oceans hold an estimated 230 billion tons of lithium, but its extraction is complicated by lithium's extreme dilution and the overwhelming presence of sodium—seawater contains 60,000 times more sodium than lithium. Conventional evaporation methods lead to salt scaling that clogs equipment, halting production. The SPSE device features a sandwich-like structure with a lithium-adsorbing core between two sun-absorbing layers. Solar energy induces evaporation, concentrating lithium ions while a unique 30-degree tilt causes the device to rock like a seesaw. This motion submerges salt crusts formed on one end, allowing natural seawater to wash them away and preventing clogging