Utilization of mineral carbonation products: current state and potential

Mineral carbonation (MC) is a form of carbon capture and storage that reacts CO2 with alkaline feedstock to securely store CO2 as solid carbonate minerals. To improve process economics and accelerate commercial deployment, research has increased around product utilization, where markets exist primarily in the construction industry. This review assesses the potential for advancing MC product utilization to decrease CO2 emissions toward neutral, or even negative, values. First, the literature surrounding the current state and challenges for indirect MC processes is reviewed, indicating that process intensification and scale‐up are important areas for further research. Alkalinity sources available for MC are examined, differentiating between those sourced from industrial processes and mining operations. Investigation of possible end uses of carbonate products reveals that further CO2 avoidance can be achieved by replacing conventional carbon‐intensive products. Companies that are currently commercializing MC processes are categorized based on the feed used and materials produced. An analysis of company process types indicates that up to 3 GtCO2 year–1 could be avoided globally. It is suggested that upcoming commercial efforts should focus on the carbonation of industrial wastes located near CO2 sources to produce precast concrete blocks. Carbonation of conventional concrete shows the highest potential for CO2 avoidance, but may face some market resistance. Carbonation of Mg silicates lacks sufficient market demand and requires the development of new high‐value products to overcome the expense of mining and feed preparation. It is suggested that research focus on enhanced understanding of magnesia cement chemistry and the development of flame‐retardant mineral fillers. © 2019 The Authors. Greenhouse Gases: Science and Technology published by Society of Chemical Industry and John Wiley & Sons, Ltd.