Carbonation behavior of reactivated recycled concrete fines containing residual sand: effects of Ca/Si ratio adjustment and activation temperature
Carbonation behavior of reactivated recycled concrete fines containing residual sand: effects of Ca/Si ratio adjustment and activation temperature
The valorization of recycled concrete fines (RCF) into reactive binders offers a sustainable solution for mitigating construction waste and carbon emissions. However, embedded sand particles hinder phase development during thermal activation. This study explores thermally activated sand-containing RCF by adjusting calcium-to-silicon ratio via limestone addition to produce reactivated cementitious materials (RCM). Carbonation-cured RCMs were analyzed for phase evolution, microstructure, and strength. Results showed that higher activation temperature with Ca addition enhanced sand reactivity and mineral formation, transitioning from α′ H-C 2S and β-C 2S below 1000 °C to low-reactivity CS or C 3S 2 at 1200 °C. Carbonation curing of RCM activated at 1000 °C with 20 wt.% limestone addition yielded the highest mechanical performance by optimizing phase reactivity, carbonation efficiency, and pore refinement, while lower strengths in other groups stemmed from insufficient CaCO 3 and silica gel. Life cycle assessment showed a 61 % CO 2 reduction compared to Portland cement, which validates thermochemical tuning for closed-loop RCF recycling.
Carbonation curing, Reactivated binders, Recycled concrete fines, Residual sand particles, Thermal activation
Ju, Yutong
729a1024-6d8b-4cbf-9e90-207b76676250
Li, Ye
86d13351-982d-46c3-9347-22794f647f86
Xian, Xiangping
27fc1b16-0ec8-466a-975c-7c4cc2b1cfd8
Liu, Tiejun
07e72a65-be75-4b13-b54d-9ed949c93470
18 December 2025
Ju, Yutong
729a1024-6d8b-4cbf-9e90-207b76676250
Li, Ye
86d13351-982d-46c3-9347-22794f647f86
Xian, Xiangping
27fc1b16-0ec8-466a-975c-7c4cc2b1cfd8
Liu, Tiejun
07e72a65-be75-4b13-b54d-9ed949c93470
Ju, Yutong, Li, Ye, Xian, Xiangping and Liu, Tiejun
(2025)
Carbonation behavior of reactivated recycled concrete fines containing residual sand: effects of Ca/Si ratio adjustment and activation temperature.
Carbon Capture Science & Technology, 18, [100557].
(doi:10.1016/j.ccst.2025.100557).
Abstract
The valorization of recycled concrete fines (RCF) into reactive binders offers a sustainable solution for mitigating construction waste and carbon emissions. However, embedded sand particles hinder phase development during thermal activation. This study explores thermally activated sand-containing RCF by adjusting calcium-to-silicon ratio via limestone addition to produce reactivated cementitious materials (RCM). Carbonation-cured RCMs were analyzed for phase evolution, microstructure, and strength. Results showed that higher activation temperature with Ca addition enhanced sand reactivity and mineral formation, transitioning from α′ H-C 2S and β-C 2S below 1000 °C to low-reactivity CS or C 3S 2 at 1200 °C. Carbonation curing of RCM activated at 1000 °C with 20 wt.% limestone addition yielded the highest mechanical performance by optimizing phase reactivity, carbonation efficiency, and pore refinement, while lower strengths in other groups stemmed from insufficient CaCO 3 and silica gel. Life cycle assessment showed a 61 % CO 2 reduction compared to Portland cement, which validates thermochemical tuning for closed-loop RCF recycling.
Text
1-s2.0-S2772656825001940-main
- Version of Record
More information
Accepted/In Press date: 14 December 2025
e-pub ahead of print date: 15 December 2025
Published date: 18 December 2025
Keywords:
Carbonation curing, Reactivated binders, Recycled concrete fines, Residual sand particles, Thermal activation
Identifiers
Local EPrints ID: 511235
URI: http://eprints.soton.ac.uk/id/eprint/511235
ISSN: 2772-6568
PURE UUID: 9628a579-f1c2-48f1-acad-e4100130a859
Catalogue record
Date deposited: 08 May 2026 16:52
Last modified: 09 May 2026 02:37
Export record
Altmetrics
Contributors
Author:
Yutong Ju
Author:
Ye Li
Author:
Xiangping Xian
Author:
Tiejun Liu
Download statistics
Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.
View more statistics