A team of scientists have discovered a way to employ humble grocery store baking soda in the capture of carbon dioxide.
The team is made up of scientists from the Lawrence Livermore National Laboratory, Harvard University and the University of Illinois at Urbana-Champaign. They developed a new carbon capture media which is made up of core-shell microcapsules, whose highly permeable polymer shell contains sodium carbonate solution, which reacts with and absorbs carbon dioxide. Sodium carbonate makes up a large part of baking soda, according to an article on cemag.com.
Capturing carbon dioxide: A new use for microcapsules
Carbon dioxide is free to pass through the shell, but the liquid is held inside. Microcapsules of this kind are used in the controlled delivery and release of pharmaceuticals and food flavoring, for example, but have never been used to capture carbon dioxide. The science behind the idea could eventually be used to reduce global warming by preventing carbon dioxide from fossil fuel burning power plants from being released into the atmosphere.
The main benefit of using carbonates is that they are not harmful to the environment. Caustic fluids such as monoethanol amine are currently used successfully in carbon capture programs, but they present an environmental risk. The fact that the fluid is encapsulated means that it will never come into contact with equipment, and the carbonate does not react with other gases as more caustic absorbents do.
Sustainability and environmental benefits
The increased surface of the capsules means that far greater amounts of carbon dioxide are absorbed, but a new kind of capture process is required. Scientists at the National energy Technology Laboratory (NETL) are currently working on an innovative process, which will work with coal or natural gas-burning power plants, and also in industrial processes such as steel and cement production.
The scientists claim that the entire process of encapsulation is more sustainable than current technology. Using sodium carbonate does not require any complex chemical processes like the production of amines does, nor does it have any recycling issues. Baking soda can be reused forever, but amines degrade over time.
