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DOE OSTI · 23206278

A parametric study of accelerated carbonation in alkali-activated slag

McCaslin, Eric R.
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Abstract

Resistance to carbonation is one important attribute that low-CO{sub 2} cement alternatives must possess, and is particularly crucial for cement alternatives subjected to aggressive CO{sub 2} concentrations such as those used in construction of oil wells and wells for below ground carbon sequestration. Here, a parametric study of alkali-activated slag (AAS) carbonation in aggressive environments has been conducted to examine (i) calcium carbonate polymorphism using X-ray diffraction (XRD) and Fourier-transform infrared (FTIR) spectroscopy, and (ii) the extent of calcium carbonate formation and CO{sub 2} adsorption using thermogravimetric analysis (TGA). A range of AASs have been studied by varying the magnesium content of the slag, the activator type (sodium hydroxide and sodium silicate), the activator concentration, and the curing time prior to carbonation. It was uncovered that both (i) magnesium from the slag and (ii) silica from the activating solution are needed to reduce the propensity for the sodium-containing calcium-alumino-silicate-hydrate gel to undergo decalcification.

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36 MATERIALS SCIENCEABSORPTION SPECTROSCOPYADSORPTIONCALCIUMCALCIUM CARBONATESCARBON DIOXIDECARBON SEQUESTRATIONCEMENTSFOURIER TRANSFORM SPECTROMETERSFOURIER TRANSFORMATIONHYDRATESINFRARED SPECTRAMAGNESIUMPARAMETRIC ANALYSISSILICASLAGSSODIUM SILICATESTHERMAL GRAVIMETRIC ANALYSISX-RAY DIFFRACTION

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BibTeXRIS

McCaslin, Eric R.. 2021-07-15. A parametric study of accelerated carbonation in alkali-activated slag. https://doi.org/10.1016/j.cemconres.2021.106454

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DOE OSTI2026

Cyclic moisture reactivation of calcium sorbents for long duration thermochemical energy storage

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36 MATERIALS SCIENCE↗