INPEX and Sumitomo Osaka Cement have begun a demonstration test of Ca-Looping technology, which captures CO2 through the circular use of calcium compounds. The initiative aims to apply the technology to large vessels, and the demonstration equipment has been installed at the National Maritime Research Institute.
On 19 October 2026, INPEX and Sumitomo Osaka Cement announced that they had begun a demonstration test of Ca-Looping technology, which they have been jointly researching since August 2023. The technology uses the characteristic of converting CO2 into calcium carbonate at ambient temperature and pressure. The demonstration equipment has been installed at the National Maritime Research Institute, where testing is being conducted.
The process consists of three stages that enable the continuous capture of CO2 through the circular use of calcium. In Process A, CO2 emitted from large vessels is captured in an alkaline solution, and the resulting CO2-containing solution is reacted with Ca(OH)2 to produce CaCO3. In Process B, the CaCO3 produced is transported to an underground storage site, where it is decomposed to release CO2 again, enabling underground storage and the production of CaO. In Process C, the regenerated Ca(OH)2 is transported to the CO2 generation site, and the cycle is repeated.
As its first stage, the technology is being developed for installation on large vessels. In the future, it is also expected to contribute to the technology’s deployment in society and the effective use of INPEX’s domestic and overseas CO2 underground storage sites. For further details, refer to INPEX’s official news release.