A research team led by James Buchen from the University of Delaware has developed a new electrochemical carbon-capture device. The system uses a battery-like structure where nickel hydroxide cathodes and anodes facilitate the conversion of carbon dioxide into carbonate or bicarbonate, which is then transported across a cell membrane.
The device operates as a chemical see-saw, where reversing the applied voltage drives the chemistry in both directions to capture and release carbon dioxide. The researchers tested a prototype consisting of nine stacked cells, each roughly half the size of a standard letter-sized sheet of paper, utilizing components adapted from fuel cell technology.
The lab-scale unit consumes approximately 0.8 megawatt-hours of electricity per ton of captured carbon dioxide. This efficiency compares favorably to existing direct air capture facilities, which typically require between 1.5 and 3 megawatt-hours per ton.
Several team members are associated with the startup RepAir Carbon, which is developing this technology. The researchers estimate the cost for an initial small pilot plant at $566 per ton of captured carbon dioxide. By applying learning rates from the lithium-ion battery industry, they project costs could fall to $92 per ton for a plant with a thousand times the pilot's capacity.
