Microstructure and carbon storage capacity of hydrated magnesium carbonates synthesized from different sources and conditions

Dong, H., Unluer, C. , Yanga, E.-H., Jin, F. and Al-Tabbaa, A. (2019) Microstructure and carbon storage capacity of hydrated magnesium carbonates synthesized from different sources and conditions. Journal of CO2 Utilization, 34, pp. 353-361. (doi: 10.1016/j.jcou.2019.07.016)

[img]
Preview
Text
190420.pdf - Accepted Version
Available under License Creative Commons Attribution Non-commercial No Derivatives.

4MB

Abstract

Recently, the mineral carbonation via the reaction of CO2 with saline aquafers received much attention as one of the most promising ways for geologic CO2 storage. This paper reports microstructure and carbon storage capacity of hydrated magnesium carbonates (HMCs) synthesized from different sources, i.e., reject brine and commercial Mg(OH)2 slurry, and under different conditions, i.e., pH (8–14) and Mg(OH)2:CO2 molar ratio (1:1–1:7). Results show that dypingite (Mg5(CO3)4(OH)2·5H2O) is the main phase forming at lower Mg(OH)2:CO2 ratios. An increase in the Mg(OH)2:CO2 ratio and/or pH leads to the precipitation of nesquehonite (MgCO3·3H2O). A unique “house of cards” texture, involving formation of the rosette-like dypingite flakes on the surface of nesquehonite needles, is discovered under elevated pH and Mg(OH)2:CO2 ratios. HMCs synthesized from reject brine exhibit a much higher carbon storage capacity of 82.6% than that produced from the commercial Mg(OH)2 slurry (43.7%). Findings from this study advance understanding of mineral recovery from reject brine and the capture and long-term storage of CO2 in the form of HMCs.

Item Type:Articles
Additional Information:The authors would like to acknowledge the financial support from the Singapore Ministry of Education Academic Research Fund Tier 2 (MOE2017-T2-1-087 (S)) for the completion of this research project.
Status:Published
Refereed:Yes
Glasgow Author(s) Enlighten ID:Unluer, Dr Cise and Jin, Dr Fei
Authors: Dong, H., Unluer, C., Yanga, E.-H., Jin, F., and Al-Tabbaa, A.
College/School:College of Science and Engineering > School of Engineering > Infrastructure and Environment
Journal Name:Journal of CO2 Utilization
Publisher:Elsevier
ISSN:2212-9820
ISSN (Online):2212-9839
Published Online:27 July 2019
Copyright Holders:Copyright © 2019 Elsevier Ltd.
First Published:First published in Journal of CO2 Utilization 34:353-361
Publisher Policy:Reproduced in accordance with the copyright policy of the publisher

University Staff: Request a correction | Enlighten Editors: Update this record