CO2 mineralisation of Portland cement: Towards understanding the mechanisms of enforced carbonation

Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaperJournal articleResearchpeer-review

  • MacIej Zajac, HeidelbergCement AG
  • ,
  • Aurore Lechevallier, HeidelbergCement AG
  • ,
  • Pawel Durdzinski, HeidelbergCement AG
  • ,
  • Frank Bullerjahn, HeidelbergCement AG
  • ,
  • Jørgen Skibsted
  • Mohsen Ben Haha, HeidelbergCement AG

Reductions of CO2 emissions associated with Portland cement production represent currently the main challenge for the cement industry. A promising approach is to substitute the traditional hydration of cement by carbonation of cement clinker for the hardening of the material in concrete production. This work is a tailor-made experimental approach to explore the mechanisms of Portland clinker carbonation under wet conditions. The carbonation is found to be fast at the beginning of the reaction, provided enough CO2 is present in the system. Particularly, the calcium silicate phases react rapidly, where the kinetics is explained by the high undersaturation of these phases. Furthermore, the carbonation reaction can be divided into three stages when the reaction is limited by the different mechanisms: Precipitation of products or dissolution of clinker or CO2. The main carbonation products are calcium carbonate and amorphous alumina silica gel. These phases precipitate in a different locations forming a special microstructural pattern.

Original languageEnglish
JournalJournal of CO2 Utilization
Volume38
Pages (from-to)398-415
Number of pages18
ISSN2212-9820
DOIs
Publication statusPublished - 2020

    Research areas

  • Calcite Silica gel, Carbonation, Kinetics Calcium silicates

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