Mitsui & Co., Ltd. (Tokyo) and Microwave Chemical Co., Ltd. (MWCC) will initiate a demonstration experiment using a pilot plant under the agreement of the joint development of microwave-based low-carbon lithium ore refining technology.
The use of electric power in the mobility sector is expanding as part of the transition to a carbon-neutral society. Many countries have designated lithium as a critical mineral because of its use in EV batteries, and there is also an increasing need to establish reliable supply networks for lithium from an economic security perspective. Lithium ore is refined using heat generated through fossil fuel combustion, and there is concern about the reduction in the large amounts of CO2 emitted during the calcination process. Therefore, it is anticipated that there will be growing demand for low-carbon lithium produced in ways that minimize the environmental impact.

The newly completed microwave refining pilot plant (source: Mitsui)
The purpose of this joint development project is to electrify the calcination process—the main source of CO2 emissions in lithium refining—and to establish the world’s first lithium refining technology using eco-friendly microwave technology and explore the potential for the implementation of this technology at new lithium mines and refining plants. In order to increase the scale of this technology, a pilot plant for conducting the demonstration experiment has been completed at the MWCC plant based in Osaka.
This pilot plant will continuously calcine lithium ore by using a microwave heating unit. In addition to a significant reduction in CO2 emissions, this method will also deliver energy savings through improved thermal efficiency. The next step will be to use this plant to conduct a demonstration experiment with a capacity of approximately 700 tons per year, in preparation for commercialization by around 2030.
Mitsui aims to achieve net zero emissions by 2050 and to halve its greenhouse gas impact by 2030 compared with the level in the fiscal year ended March 2020. Through this project, Mitsui will contribute to the realization of a carbon-neutral society by establishing a reliable lithium supply chain.
MWCC sees the real-world implementation of this new lithium ore refining technology as a step toward the achievement of carbon neutrality under its C NEUTRAL™ 2050 Design concept, and as a way to realize its vision “To reinvent a chemical industry which has remained unchanged over a century and transform the world of manufacturing. To make the microwave process a global standard.”