Li Jiankun, Gu Xiaowei, Yang Bohan, Wang Shenyu, Hu Zhihang, Hu Ziyang, Ge Xiaowei
Science and Technology Innovation Center of Smart Water and Resource Environment, Northeastern University, Shenyang 110819, China.
Liaoning Institute of Technological Innovation in Solid Waste Utilization, Shenyang 110819, China.
Materials (Basel). 2025 Sep 9;18(18):4231. doi: 10.3390/ma18184231.
Basic magnesium sulfate cement (BMSC) has attracted increasing attention as a low-carbon alternative to traditional Portland cement. Therefore, this study investigates the feasibility of using carbonated boron mud (CBM), an industrial solid waste, as a partial substitute for magnesium oxide (MgO) in BMSC. Prior to its incorporation into the cementitious matrix, boron mud (BM) underwent rapid carbonation treatment to improve its reactivity, microstructure compatibility, and CO sequestration potential. Experimental results from macroscopic and microscopic analyses confirmed the effectiveness of the carbonation process, showing that the carbonate ions carried by the CBM were successfully incorporated into the cementitious system. These carbonate ions reacted with MgO to form stable magnesium carbonate phases, effectively suppressing the formation of magnesium hydroxide (Mg(OH)), which typically detracts from strength and stability. Compared to BMSC specimens containing untreated BM, the CBM-modified BMSC exhibited significantly improved mechanical performance and excellent volume stability. Furthermore, the carbonation pre-treatment effectively mitigated volumetric instabilities associated with rapid MgO hydration, thereby promoting a more favorable environment for the formation of the crucial 5·1·7 phase (5Mg(OH)·MgSO·7HO). Overall, this research presents a promising strategy for producing CBM-BMSC, offering a sustainable approach to CO utilization and enhancing the volume stability of magnesium-based cements, providing a new direction for improving the sustainability of the concrete industry and advancing the development of magnesium cements.
碱式硫酸镁水泥（BMSC）作为传统波特兰水泥的低碳替代品，已引起越来越多的关注。因此，本研究探讨了将工业固体废物碳酸化硼泥（CBM）作为BMSC中氧化镁（MgO）的部分替代品的可行性。在将硼泥（BM）掺入水泥基基体之前，对其进行了快速碳酸化处理，以提高其反应活性、微观结构相容性和二氧化碳封存潜力。宏观和微观分析的实验结果证实了碳酸化过程的有效性，表明CBM携带的碳酸根离子成功掺入水泥体系。这些碳酸根离子与MgO反应形成稳定的碳酸镁相，有效抑制了氢氧化镁（Mg(OH)）的形成，而氢氧化镁通常会降低强度和稳定性。与含有未处理BM的BMSC试样相比，CBM改性的BMSC表现出显著改善的力学性能和优异的体积稳定性。此外，碳酸化预处理有效地减轻了与MgO快速水化相关的体积不稳定性，从而为关键的5·1·7相（5Mg(OH)·MgSO·7H₂O）的形成创造了更有利的环境。总体而言，本研究提出了一种生产CBM-BMSC的有前景的策略，为二氧化碳利用提供了一种可持续的方法，并提高了镁基水泥的体积稳定性，为提高混凝土行业的可持续性和推动镁水泥的发展提供了新的方向。
