• Kyodo


Researchers at Saga University’s Institute of Ocean Energy have begun extracting tiny amounts of lithium from seawater — at a rate of 1 gram per day — and hope to be the first in the world to commercialize the process.

The operation is being conducted by the institute’s plant in the city of Imari, Saga Prefecture.

While lithium has been extracted from seawater at various laboratories, this marks the first attempt to commercialize the process, according to Kazuharu Yoshizuka, a professor in the University of Kitakyushu environmental engineering department.

The Saga University plant, which was completed last summer, has already extracted about 30 grams of lithium chloride from 140,000 liters of seawater in about 30 days.

Japan currently extracts lithium from ore imported from China, Australia and South America. Yoshizuka said Japan could domestically supply lithium if it can develop an efficient and cost-effective extraction system.

“This is not a dream,” said Yoshizuka, who has been involved in the Saga project.

Scientists say seawater may contain 230 billion tons of lithium, while lithium deposits on land are estimated at 14 million tons.

Commercializing the seawater extraction process, however, has been hampered by the low concentration of lithium in seawater — about 0.1 to 0.2 mg per 1 liter of seawater.

Saga University researchers use a device containing specially processed manganese dioxide crystals to absorb the lithium from seawater.

The plant has been extracting lithium from seawater in Imari Bay since February and has obtained lithium chloride with about 90 percent purity.

The researchers also plan to use waste water from nuclear and industrial plants as well as lithium-rich spring water to boost the extraction efficiency.

Lithium, the lightest metal, is present in ores, seawater and spring water. It has a wide range of applications, including in the manufacture of semiconductors and as an ingredient in drugs for the treatment of bipolar disorders and other types of mental illness.

In recent years, lithium has been used extensively in long-life batteries to power mobile phones and other electronic gadgets.