A large-scale plant for producing fluorite, completed by Sumitomo Densetsu and Professor Shinji Yasui of Nagoya Institute of Technology (center), in Nagoya. (Courtesy of Sumitomo Densetsu)
Sumitomo Densetsu and Nagoya Institute of Technology Professor Shinji Yasui have completed a plant that produces high-purity fluorite, an essential mineral for semiconductor manufacturing.
What makes this facility unique is its ability to recover sulfur hexafluoride (SF6), a fluorinated gas used as an insulator in electrical equipment, and convert it into fluorite, creating a new domestic production route. This project represents the world's first commercially viable process of its kind, reducing dependency on imported fluorite and improving Japan's supply chain reliability.
Fluorite is the main raw material used to produce fluorine. Fluorine-based chemicals made from it are used in products such as air conditioners and are indispensable to semiconductor manufacturing.
Because fluorite is essential to high-tech manufacturing, Japan has designated it a "specified critical product" under its Economic Security Promotion Act. Its supply stability is directly linked to national economic security.
Yet supply risks persist. In 2025, China produced about 60% of global natural fluorite output. When Mexico and Mongolia are added, the three countries together account for roughly 90%.
Recycling SF6 Into a Critical Mineral
Japan's Cabinet Office has warned that any disruption in fluorite supplies could halt nearly all semiconductor production, thereby threatening Japan's economic security. The office notes that finding substitutes is difficult and explains that Japan imports all of its domestic needs, making the country excessively dependent on overseas sources.
Fluorine also creates a potent greenhouse effect when released into the atmosphere. At present, some waste from fluorine-based chemical processes is landfilled as sludge containing low concentrations of fluorite.
This practice has prompted efforts to recover fluorine more efficiently, extract fluorite, and reuse it, an approach seen as advancing both climate goals and economic security.
The newly completed plant recovers SF6, a fluorine compound used as an insulating gas in high-voltage power equipment, and converts it into fluorite with a purity exceeding 99%.
In the process, a gas mixture of SF6 and hydrogen is heated to 1,000-1,200 degrees Celsius. It then passes through a 200-degree low-temperature stabilization furnace packed with calcium carbonate, where fluorite forms. The system can produce about 3.2 tons of fluorite a year from two tons of SF6.
A World-First Plant Nears Commercial Use
A plant capable of producing fluorite from SF6 at a practical-use level marks the first of its kind in the world. The team will move it to Takaoka, Toyama Prefecture, in April, to a Sumitomo Densetsu partner company. After trial runs, stakeholders expect full-scale operations to begin around July.
According to Japan's Ministry of Economy, Trade and Industry, the amount of SF6 held domestically is estimated at 9,500 tons.
"Fluorine compounds that have been disposed of as waste are turned into a resource through the production of fluorite," Professor Yasui said. "This can help realize a circular economy by creating a cycle from resource production to consumption and recovery, and it will also lead to a reduction in greenhouse gases."
Yasui began developing the plant about 20 years ago while working at the Central Research Institute of Electric Power Industry, though few paid attention to the project at the time. Sumitomo Densetsu later partnered with Yasui, concluding that they could achieve dual benefits: higher corporate value and additional earnings from recovering and reusing SF6.
Remaining Hurdles
One challenge to commercialization, however, is the low purchase price of fluorite. Sumitomo Densetsu aims to recoup its investment by tapping Japan's J-Credit Scheme, under which companies and local governments can buy government-certified reductions in carbon dioxide emissions.
Daikin Industries also reuses fluorite recovered during the disposal of fluorochemical products. AGC likewise reuses recovered fluorite, but has focused on raising its purity, producing what it calls "recycled fluorite" from wastewater at plants that handle fluorine.
AGC has also boosted the value of its products by obtaining third-party certification for the share of recycled fluorite used in its fluorine-based products.
Ensuring the economic security benefits of domestically produced fluorite will require coordination among a broad range of stakeholders, including the government.
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(Read the article in Japanese.)
Author: Yohei Ushijima, The Sankei Shimbun
