Enhancing the performance of MgO-activated slag-fly ash mixes by accelerated carbonation

Dung, N.T., Hooper, T.J.N. and Unluer, C. (2020) Enhancing the performance of MgO-activated slag-fly ash mixes by accelerated carbonation. Journal of CO2 Utilization, 42, 101356. (doi: 10.1016/j.jcou.2020.101356)

Abstract

This study focused on the development of reactive MgO (RM) activated-GGBS binders containing fly ash (FA). Performance of these binders was aimed to be improved by enhancing the hydration of RM and dissolution of GGBS and FA via high temperature pre-curing (HTPC); and conversion of unreacted phases into carbonates via carbonation. Spherical FA particles mitigated inter-particle surface frictions and improved flow. Although the use of HTPC accelerated the hydration of MgO, rapid precipitation of brucite hindered the dissolution of GGBS and FA and formation of associated hydration products. Transformation of RM into hydrated magnesium carbonates (HMCs) under carbonation led to significant improvements in sample performance via the pore filling effect and binding strength provided by HMCs, despite the degradation of ettringite and C-(A)-S-H during carbonation. Inclusion of 12 % FA resulted in comparable strengths to the control sample, highlighting the feasibility of incorporating FA within RM activated-GGBS samples without compromising performance.

• Item Type: Articles
• Additional Information: The authors would like to acknowledge the financial support from the Singapore MOE Academic Research Fund Tier 1 (RG 95/16) and the assistance of Mr. Douglas Kieo Yong Qiang for the completion of this research project.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Unluer, Dr Cise

Creator Roles

Unluer, C.: Funding acquisition, Methodology, Resources, Writing – original draft, Writing – review and editing, Supervision, Project administration

• Authors: Dung, N.T., Hooper, T.J.N., and Unluer, C.
• 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: 02 November 2020
• Copyright Holders: Copyright © 2020 Elsevier
• First Published: First published in Journal of CO2 Utilization 42:101356
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher