Binding Carbon Dioxide Using Broken Concrete

(ETH Zurich, August 24, 2020)

In an effort to reduce construction-related emissions, ETH spin-off Neustark recently developed a new technology that sustainably binds CO₂ in the pores and on the surface of concrete granulate as limestone, which can subsequently be mixed into fresh concrete as a replacement for sand and gravel. Therefore, less cement is required for construction, which in turn improves its carbon balance, as some production-related emissions can be avoided. Furthermore, by employing their additional trick of capturing CO₂ from the air, Neustark founders Johannes Tiefenthaler and Valentin Gutknecht contend that they can even reverse CO₂ emissions. Considering that cement production worldwide releases around four times as much CO₂ into the air as global air traffic, the value of this novel approach cannot be understated.