Cement mixing process sequesters carbon in a neutral and strength-enhancing way

Edit Hook

CO2 is absorbed by various organisms, i.e., plants and algae, to synthesize structural materials such as cellulose. Drawing inspiration from this ability to both sequester carbon and use it to strengthen material, TecEco of Australia has developed a novel type of cement called Eco-Cement. Eco-Cement is doped with magnesia (also known as magnesium oxide or MgO) which reacts with water during the cement mixing process to form magnesium hydroxide. The porous microscopic architecture of the setting cement allows CO2 to permeate through the material and react with the magnesium hydroxide to form magnesium carbonate, a mineral that confers extra strength and rigidity. In forming magnesium carbonate, the CO2 is effectively trapped as a solid mineral within the concrete. Since magnesia is produced by baking magnesium cabonate ore (a CO2 releasing process), the cement is essentially carbon neutral (disregarding processes like baking and transportation). For comparison, traditional cement is a net producer of CO2. If carbon capture is implemented during the magnesia production phase, Eco-Cement is a net carbon appropriator.

Key Differentiators

TecEco’s Eco-Cement could be used as an ubiquitous building material that traps atmospheric CO2. This not only prevents the CO2 release from traditional cements but also goes a step further and allows for more filler materials to be used as opposed to wasted..

Biomimicry Story

This technology sequesters carbon like a number of other natural processes, but on the other hand, it does so using magnesia which is not a method found in nature. This strategy involves using magnesium to strengthen other materials.

Challenges Solved

Traditional Portland cement is made with alkaline quicklime. The production of which (from lime) releases a great deal of CO2 into the atmosphere (both from chemical reactions and the intense heat required). Moreover, filler materials often react with the alkaline material to create structural weakness in the set concrete after some time has passed.

Edit Summary