Adding sodium bicarbonate—baking soda—in powder form to concrete production could reduce the carbon footprint of the ubiquitous building material by 15%, without compromising mechanical performance, according to a study at the Massachusetts Institute of Technology. In addition to sequestering carbon, an advantage to adding baking soda is a faster-setting concrete mix that can allow formwork to be removed earlier, reducing the time required to complete a structure, says Admir Masic, the study's lead researcher and an associate professor in MIT’s department of civil and environmental engineering.
“The importance of this research is our understanding of the capacity of cement to mineralize CO2 in the early stages of making concrete,” without affecting the material’s mechanical properties, says Masic, lead author of the article "Cementing CO2 into C-S-H: A step toward concrete carbon neutrality," published March 28 in the journal PNAS Nexus.