Review of carbon removals through mineral carbonation (EU CRCF)

This technical review concerns the sequestration of CO₂ in the form of solid carbonate minerals, a process referred to as mineral carbonation. We focus in particular on cement-based building materials, but also consider alkaline industrial by-products such as metallurgical slags that contain calcium oxide or calcium hydroxide, and mine tailings containing silicates and other alkaline compounds. These materials carbonate naturally when exposed to atmospheric CO2 and moisture; ‘enhanced carbonation’ is where the process is sped up by active intervention, and this could be a candidate for recognition under the CRCF. The review covers the underlying chemistry of carbonation, the environmental factors that influence its rate, and the critical challenge of quantifying the natural carbonation baseline.

The review was conducted by Cerulogy, and was presented alongside evidence from external experts and from the CRCF Expert Group on Permanent Carbon Removals at a European Commission workshop.