Kwasny, J, Basheer, PAM orcid.org/0000-0002-0835-8029, Russell, MI et al. (3 more authors) (2014) CO2 sequestration in cement-based materials during mixing process using carbonated water and gaseous CO2. In: Olek, J and Weiss, J, (eds.) ICDCS; Proceedings of the 4th International Conference on the Durability of Concrete Structures. ICDCS 2014, 24-26 Jul 2014, West Lafayette, Indiana, USA. Purdue Scholarly Publishing Services , pp. 72-79. ISBN 978-1-62671-018-4
Abstract
This paper presents selected findings from a recently completed research project, aimed at the investigation of CO2 sequestration in cement-based materials during the early stages of hydration when the cement paste is being mixed. Portland cement pastes were carbonated during the mixing process, using both carbonated water and gaseous CO2, and their properties were compared to the control non-carbonated mix. All mixes were prepared in a purpose-designed chamber that permitted carbonated water and gaseous CO2 to be mixed with the cementbased materials during the mixing process, without losses of CO2 to the external environment. Temperature measurements taken of the samples during mixing were used to evaluate the influence of carbonation on the properties of fresh pastes and their early hydration. Changes in the composition of the hardened pastes, due to the above- mentioned processes, were studied using thermogravimetric (TG) analysis, X ray diffractometry (XRD), and Fourier transform infrared spectroscopy (FTIR). Scanning electron microscopy (SEM) in conjunction with energy-dispersive X-ray spectroscopy (EDXS) were used to investigate physical (morphological) and chemical differences between non-carbonated and carbonated samples. It was found that, when compared to the non-carbonated mixes, the rate of the initial hydration of carbonated pastes increased, but the later hydration rate was decreased dramatically. TG, XRD, and FTIR spectroscopy revealed a substantial increase in the CaCO3 content and decrease in the Ca(OH)2 content in carbonated pastes. SEM showed substantial differences in the microstructure of the carbonated mixes when compared to the noncarbonated ones; needle- and lichen-like hydrates, with a high content of CO2, covered the surface of the fractured carbonated samples.
Metadata
Item Type: | Proceedings Paper |
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Authors/Creators: |
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Editors: |
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Keywords: | carbonated water, carbonation, CO2 sequestration, cement hydration, TG, XRD, FTIR, SEM. |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Civil Engineering (Leeds) > Institute for Resilient Infrastructure (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 22 Mar 2018 11:49 |
Last Modified: | 22 Mar 2018 11:49 |
Published Version: | https://docs.lib.purdue.edu/icdcs/2014/carbonation... |
Status: | Published |
Publisher: | Purdue Scholarly Publishing Services |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:122439 |