Significant challenges have been found when using MOC, such as its poor water resistance and its ability to corrode steel.
CEMENTING A CARBON-
NEUTRAL FUTURE A CARBON-NEUTRAL CEMENT HAS BEEN DEVELOPED TO DRASTICALLY REDUCE EMISSIONS, BUT ITS POOR WATER RESISTANCE AND STEEL CORROSION PROPERTIES HAVE RESTRICTED ITS USE – UNTIL NOW.
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n 2018, the BBC reported that the creation of cement is the source of about eight per cent of the world’s carbon dioxide emissions. If the cement industry was a country, it would be the third largest emitter in the world, behind only China and the US, the article states. In an attempt to reduce emissions from the sector, an alternative cement has been created known as MOC (magnesium oxychloride cement). This cement is made from mixing magnesium oxide (MgO) powder and a concentrated solution of magnesium chloride (MgCl₂). A Chemical Review paper from ASC
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Publications by Sam A. Walling and John L. Provis at the University of Sheffield, UK found that the ingredient MgO offers a unique potential to develop carbon neutral, carbon-negative concrete or concrete products by absorbing carbon dioxide. Significant challenges have been discovered when using MOC, such as its poor water resistance and its ability to corrode steel. These hurdles have restricted the cement from being widely used in the building of structures, as steel is commonly used for reinforcement and outdoor structures will be attacked by water when raining.
Creating large concrete structures such as railway stations or airport terminals requires steel reinforcement.
