PERTANIKA JOURNAL OF SCIENCE AND TECHNOLOGY

This study explores the potential of using calcium hydroxide (Ca(OH)₂) derived from Carbide Lime Waste (CLW) as a high-volume cement replacement (40%–70% by volume) in mortar. The mortar was subjected to accelerated carbon dioxide (CO₂) curing to enhance carbonation capture while maintaining the desired strength, promoting more sustainable construction practices. The optimum high-volume mortar was further analysed to examine its long-term properties under various postconditioning treatments, including water, wet gunny, and air curing, in terms of calcium carbonate (CaCO3) formation and late-age strength. The physical properties, such as water absorption and mechanical properties, including compressive, flexural, and splitting tensile strengths, were evaluated. CO2 capture performance was assessed through carbonation depth testing, and microstructural analysis was performed using Thermogravimetric analysis (TGA) and X-ray diffraction (XRD). Results showed that CLW70 exhibited the best mix design, achieving 100% carbonation depth and 70% CaCO3 formation within 7 days of accelerated CO2 curing. Compressive strength increased from 2.62 MPa on day 1 to 17.01 MPa on day 7. XRD analysis indicated that air curing was the most effective postconditioning treatment, resulting in the highest CaCO3 peaks. Accelerated CO2 curing also reduced water absorption, and mechanical strength improved with curing age, demonstrating that the CaCO3 formed during the carbonation process densified the CLW mortar after 7 days of curing.

• Adamu, M., Ibrahim, Y. E., Al-Atroush, M. E., & Alanazi, H. (2021). Mechanical properties and durability performance of concrete containing calcium carbide residue and nano silica. Materials, 14(22), 1–28. https://doi.org/10.3390/ma14226960
  
  ASTM C109/C109M-02. (2012). Standard test method for compressive strength of hydraulic cement mortars. Annual Book of ASTM Standards, 04(C), 9. https://doi.org/10.1520/C0109
  
  ASTM C348-21. (2021). Standard test method for flexural strength of hydraulic-cement mortars. Annual Book of ASTM Standards, 04(1), 1–5. https://doi.org/10.1520/C0348-08.2
  
  Cizer, Ö., Rodriguez-Navarro, C., Ruiz-Agudo, E., Elsen, J., Van Gemert, D., & Van Balen, K. (2012). Phase and morphology evolution of calcium carbonate precipitated by carbonation of hydrated lime. Journal of Materials Science, 47(16), 6151–6165. https://doi.org/10.1007/s10853-012-6535-7
  
  Gloria, A. C., Ogbonnaya, O. D., & Olujide, A. O. (2017). Flexural and split tensile strength properties of lime cement concrete. Civil and Environmental Research, 9(3), 10-16–16.
  
  Li, L., & Wu, M. (2022). An overview of utilizing CO2 for accelerated carbonation treatment in the concrete industry. Journal of CO2 Utilization, 60(3), Article 102000. https://doi.org/10.1016/j.jcou.2022.102000
  
  Li, X., & Ling, T. C. (2020). Instant CO2 curing for dry-mix pressed cement pastes: Consideration of CO2 concentrations coupled with further water curing. Journal of CO2 Utilization, 38, 348–354. https://doi.org/10.1016/j.jcou.2020.02.012
  
  Liu, P., Chen, Y., Yu, Z., & Zhang, R. (2019). Effect of temperature on concrete carbonation performance. Advances in Materials Science and Engineering, 2019, 1–7. https://doi.org/10.1155/2019/9204570
  
  Liu, Z., & Meng, W. (2021). Fundamental understanding of carbonation curing and durability of carbonation-cured cement-based composites: A review. Journal of CO2 Utilization, 44, Article 101428. https://doi.org/10.1016/j.jcou.2020.101428
  
  Lorca, P., Calabuig, R., Benlloch, J., Soriano, L., & Payá, J. (2014). Microconcrete with partial replacement of Portland cement by fly ash and hydrated lime addition. Materials and Design, 64, 535–541. https://doi.org/10.1016/j.matdes.2014.08.022
  
  Lu, B., Drissi, S., Liu, J., Hu, X., Song, B., & Shi, C. (2022). Cement and concrete research effect of temperature on CO2 curing, compressive strength and microstructure of cement paste. Cement and Concrete Research, 157, Article 106827. https://doi.org/10.1016/j.cemconres.2022.106827
  
  Luo, K., Cheng, X., Li, J., Lu, Z., Deng, X., Hou, L., & Jiang, J. (2022). Performance of hydraulic lime by using carbide slag. Journal of Building Engineering, 51, Article 104208. https://doi.org/10.1016/j.jobe.2022.104208
  
  Ma, H. (2014). Mercury intrusion porosimetry in concrete technology: Tips in measurement, pore structure parameter acquisition and application. Journal of Porous Materials, 21(2), 207–215. https://doi.org/10.1007/s10934-013-9765-4
  
  Nwankwo, C. O., Bamigboye, G. O., Davies, I. E. E., & Michaels, T. A. (2020). High volume Portland cement replacement: A review. Construction and Building Materials, 260, Article 120445. https://doi.org/10.1016/j.conbuildmat.2020.120445
  
  Roy, S. K., Poh, K. B., & Northwood, D. O. (1999). Durability of concrete - Accelerated carbonation and weathering studies. Building and Environment, 34(5), 597–606. https://doi.org/10.1016/S0360-1323(98)00042-0
  
  Sharma, D., & Goyal, S. (2018). Accelerated carbonation curing of cement mortars containing cement kiln dust: An effective way of CO2 sequestration and carbon footprint reduction. Journal of Cleaner Production, 192, 844–854. https://doi.org/10.1016/j.jclepro.2018.05.027
  
  Wu, H., Liang, C., Xiao, J., & Ma, Z. (2021). Properties and CO2-curing enhancement of cement-based materials containing various sources of waste hardened cement paste powder. Journal of Building Engineering, 44, Article 102677. https://doi.org/10.1016/j.jobe.2021.102677
  
  Xu, Z., Zhang, Z., Huang, J., Yu, K., Zhong, G., Chen, F., Chen, X., Yang, W., & Wang, Y. (2022). Effects of temperature, humidity and CO2 concentration on carbonation of cement-based materials: A review. Construction and Building Materials, 346, Article 128399. https://doi.org/10.1016/j.conbuildmat.2022.128399
  
  Zhang, D., Cai, X., & Shao, Y. (2016). Carbonation curing of precast fly ash concrete. Journal of Materials in Civil Engineering, 28(11), Article 04016127. https://doi.org/10.1061/(asce)mt.1943-5533.0001649
  
  Zhang, G., Peng, G. F., Zuo, X. Y., Niu, X. J., & Ding, H. (2023). Adding hydrated lime for improving microstructure and mechanical properties of mortar for ultra-high performance concrete. Cement and Concrete Research, 167, Article 107130. https://doi.org/10.1016/j.cemconres.2023.107130