Natural carbonate has been a basic building material for centuries, but synthetic carbonate is a modern and robust building material that is created by mineral carbonation.
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Mineral carbonation (or mineral sequestration) is one of the largest and most energy-efficient ways to use carbon dioxide2. By 2040, Australia-based Mineral Carbonation International aims to store 1 billion tons of carbon dioxide2 in building materials.
During the chemical process, CO2 It reacts with metal oxides such as magnesium or calcium oxides to form carbonates. It is used to take waste carbon dioxide2 and making building materials instead of releasing harmful greenhouse gases into the atmosphere and exacerbating global warming.
Since the chemistry of making carbonates based on calcium and magnesium is well understood, solid carbonates are widely used in building materials. Carbonation allows large amounts of carbon dioxide2 It is adsorbed by substances by incorporating chemically into a stable mineral carbonate as a binding agent.
The process achieves significant carbon dioxide2 Absorption is about 7-12% according to a published study led by S. Monkman and Y. Shao. It occurs thermodynamically, requiring relatively little external energy during the process, which makes it more sustainable. The results are high quality as well. Gas cement materials that capture carbon dioxide2 It can result in high strength building materials.
What is mineral carbonation?
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A normal process in the heart
Mineral carbonation is used in the construction industry, but it occurs naturally in underground rocks. It is a geological weathering process where stable carbonate is formed through the reaction of carbon dioxide2 With natural oxides or silicates such as magnesium, iron and calcium. Igneous rocks that use naturally abundant silicate minerals such as olivine and serpentine contribute to the mineral carbonation, both naturally and artificially, to create building materials.
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A study published in Nature, led by Dr. Tim Tomkinson, explains “Carburation is the mediated replacement of silicate minerals by water, such as olivine, with carbonates, which is common in the Earth’s crust. This reaction can remove large amounts of carbon dioxide from the atmosphere and store it over geological timescales..“
Plasterboard can be made by incorporating carbon dioxide2 With serpentinite. This will be a negative emission building material, after storing more carbon dioxide2 It contains what was used to make it.
According to a review of mineral carbonization technologies for CO2 sequestration2, Mineral carbonation is a promising form of carbon capture and storage (CCS) when storage in geological structures is not considered viable. However, there are some limitations, because it highlights that “The technology is still in its infancy and transportation and storage costs are still higher than geological storage in sedimentary basins ($17 instead of $8 per ton CO2).2) … its application is currently limited due to its high costs … HEnergy use, reaction rate and material handling are the main factors hindering the success of this technology. “
However, recent developments in scientific research show the potential for lowering metal carbonate costs, making it an economical and viable solution in the future.
The main challenges of its application in the construction industry also relate to the slow decomposition (dissolving) that occurs in materials and the energy requirements involved in mineral processing. However, the restrictions do not mean that mineral carbonation does not bode well for removing carbon from the building construction sector.
Long-term sustainable benefits
Sustainability in building construction is enhanced when concrete is crushed to aggregate, due to the higher surface area of small pieces, allowing for more carbon dioxide2 to be absorbed. More from CO2 It is absorbed by the aggregate when exposed to rain, due to chemical leaching that may occur, and when the aggregate is recycled for paving or even pottery. The process remains ecological even at the end of its life cycle.
Mineral carbonate absorbs nearly a third of carbon dioxide2 It is emitted when making cement, which reduces carbon dioxide2 The impact of cement use in industry. The sustainability of the system can extend further, as alkaline waste from industry can also be used to carbonize metals, such as ash from waste incineration or slag from steelmaking.
Mineral Carbonation International has designed and built three carbon reactor systems, including the first global reference pilot plant in Newcastle, Australia, to convert waste materials and greenhouse gas emissions from diverse industrial processes.
References and additional reading
carbonation of concrete [Online]. concrete center. Available at: https://www.concretecentre.com/Performance-Sustainability/Circular-economy/Whole-life/Carbonation-of-concrete.aspx
Tomkinson, T., Lee, M., Mark, D. et al. (2013). Mars company reservation2 by metal carbonation. nat common 4, 2662. Available at: https://doi.org/10.1038/ncomms3662
A. Sanna, M. Uibu, G. Caramanna, R. Kuusik and M. M. Maroto-Valer. (2014) Review of mineral carbonation techniques for carbon dioxide sequestration2. Science. pastor company, 43, 8049-8080. Available at: https://pubs.rsc.org/en/content/articlehtml/2014/cs/c4cs00035h
mineral carbonation [Online]. Direct science. Available at: https://www.sciencedirect.com/topics/engineering/mineral-carbonation
S. Monkman and Y. Shao (2006). Evaluation of the carbonization behavior of cementitious materials. J Matter. Sword. meadow. 18, 768-776. https://doi.org/10.1061/(ASCE)0899-1561(2006)18:6 (768)
Bruce J Miller. (2011) 10 – Carbon dioxide capture and storage. Clean Coal Engineering Technology, Butterworth-Heinemann, pp. 483-511, ISBN 9781856177108. Available at: https://doi.org/10.1016/B978-1-85617-710-8.00010-8.
Mineral carbonation for the production of building materials [Online]. Chapter 5. National Academies Press. Available at: https://www.nap.edu/read/25232/chapter/5
An expert explains: How to convert industrial carbon emissions into building materials [Online]. We are the forum. Available at: https://www.weforum.org/agenda/2020/11/an-expert-explains-how-to-turn-carbon-into-useful-building-materials/