Chemical Research and Climate Change as Drivers in the Commercial Adoption of Alkali Activated Materials

Portland cement production has been identified as a primary contributor to the world’s Greenhouse gas emissions, calculated at around 5–8% of all manmade emissions worldwide. The majority of these emissions are inherent to the chemistry of cement and the high-temperature processing required for its synthesis, and so can only be avoided by radical changes in construction materials chemistry and synthesis pathways. Inorganic polymer (including “geopolymer”) binders provide an alternative to traditional cements with approximately 80% less CO2 emissions, and are derived from industrial waste materials such as fly ash and metallurgical slags, which additionally provide a means of valorizing these wastes. This paper reviews the technical and commercial factors driving the growing commercial adoption of geopolymer technology, and explains that an understanding of the chemistry and mechanisms of geopolymer synthesis is pivotal for the optimal mix design of “green” concretes in industry. Demand pull by a carbon conscious market at a time of growing public awareness of climate change continues to be the key driver for the short term adoption of geopolymer concrete. A detailed chemical understanding of the properties of geopolymers, such as setting time, workability and durability, plays an enabling role in the commercialization process.

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