KAIST and MIT team turns seawater CO2 into stable carbonate with low scaling

A KAIST-led team working with MIT researchers developed an electrochemical dissolved ocean carbon removal technology that converts carbon dioxide dissolved in seawater into calcium carbonate for long-term storage, phys.org reported. The ocean absorbs about 30% of human carbon dioxide emissions. Removing dissolved inorganic carbon from seawater can let the ocean take up more CO2 from air. Prior systems struggled with mineral scaling that clogs electrodes and raises energy and maintenance costs. The group built a hollow fiber electrode assembly of bundled thread-like electrodes so minerals form away from the electrode surface while hydrogen bubbles scrub the surface. In tests with Jeju lava seawater, the device ran continuously for more than 120 hours, removed 80-90% of dissolved inorganic carbon, and cut electricity use by up to 54% versus existing methods. The process also produced high-purity hydrogen and magnesium hydroxide. The paper was published in Advanced Energy Materials. The work is led by Professor Dong-Yeun Koh at KAIST with Professor T. Alan Hatton's group at MIT.