Scientists at the Department of Energy's Oak Ridge National Laboratory (ORNL) have developed a process that removes CO2 from coal-burning power plant emissions in a way that is similar to how soda lime works in scuba diving rebreathers. Their research, published January 31 in the journal Chem, offers an alternative but simpler strategy for carbon capture and requires 24% less energy than industrial benchmark solutions.
Soda lime is a solid off-white mixture of calcium and sodium hydroxides used in scuba rebreathers, submarines, anesthesia, and other closed breathing environments to prevent the poisonous accumulation of CO2 gas. The mixture acts as a sorbent (a substance that collects other molecules), turning into calcium carbonate (limestone) as it amasses CO2. The ORNL team's CO2 scrubber works in essentially the same way to treat the CO2-rich flue gas released by coal-burning power plants -- although advancing carbon-capture technology was not always their objective.
"We initially stumbled into this research by accident," says senior author Radu Custelcean, a research scientist at ORNL.To read more, click here.