One of the serious threats faced by humanity at present is global warming. The emissions of CO2 is often considered as the primary reason for global warming. Around 8% of the overall CO2 emissions is caused by cement industry which manufactures cement, the second most utilized resource by humanity after water. With the global cement production expected to increase significantly due to higher demand in developing countries, there is a greater need to develop alternative cementitious materials with reduced CO2 emissions. Reactive magnesia oxide cements (RMC) have been gaining attention recently because of its low synthesis temperature and CO2 absorption features. Additionally, MgO required (for RMC cement manufacture) can be obtained from industrial side streams, thereby promoting circular economy (For example, there are many Mg-rich industrial side streams in Finland like talc mine wastes, phlogopite, soap stone, etc). However, there is a drawback for RMC cements: The product phase of RMC consists of Mg carbonate phases, and these carbonates are known to have stability issues, thereby affecting the durability of the cement. One solution is to add a secondary phase to form a composite type of material and stabilize the Mg carbonate phase. Mg silicate hydrate (M-S-H) is a potential phase that could be added to improve the stability of Mg carbonate phase. M-S-H phase is known to possess high durability in aggressive environment and can hence provide stability to Mg carbonate phase. The project also involves collaboration of Associate Prof./Reader Cise Unluer, whose research group at University of Glasgow aims at contributing to sustainable built environment through development of novel and functional constructional materials with high performance and durability. In short, this project proposal deals with development of a novel and durable Mg carbonate-silicate composite cement with CO2 absorption features while promoting the concepts of circular economy.

2022