Wang Yanrong, Zhen Zhilei
College of Urban and Rural Construction, Shanxi Agricultural University, Mingxian South Road 1st, Taigu, Jinzhong 030800, China.
Materials (Basel). 2024 Aug 17;17(16):4085. doi: 10.3390/ma17164085.
This study aimed to decipher the influence of red mud on the mechanical properties, pore structure, and microstructure of basic magnesium sulfate cements (BMSCs). The results showed that BMSC prepared with an appropriate addition of red mud exhibited improved mechanical properties and yielded the highest compressive strength of 94.54 MPa after curing for 28 days. Adding red mud reduced the total porosity and optimized the pore structure of BMSC. The microstructure and hydration products of the specimens were examined using X-ray diffraction, scanning electron microscopy, and energy-dispersive spectroscopy. The results illustrate that the addition of 50% red mud did not affect the amount of the main strength phase 5-1-7 produced in BMSC. It could also reduce the residual amount of MgO and the generation of Mg(OH). The red mud and the M-S-H gel generated by the reaction between active SiO and α-MgO in the red mud together filled the pore structure of BMSC, making its microstructure denser and higher-strength. This study aims to improve the comprehensive use of red mud, and the results show that red mud can improve the mechanical properties of BMSCs, protecting the environment and simultaneously reducing BMSC production costs to create good economic benefits.
本研究旨在阐明赤泥对碱式硫酸镁水泥（BMSC）力学性能、孔隙结构和微观结构的影响。结果表明，适量添加赤泥制备的BMSC力学性能得到改善，养护28天后抗压强度最高可达94.54MPa。添加赤泥降低了BMSC的总孔隙率并优化了其孔隙结构。使用X射线衍射、扫描电子显微镜和能谱对试样的微观结构和水化产物进行了检测。结果表明，添加50%的赤泥不影响BMSC中主要强度相5-1-7的生成量。它还可以减少MgO的残留量以及Mg(OH)的生成。赤泥与赤泥中活性SiO与α-MgO反应生成的M-S-H凝胶共同填充了BMSC的孔隙结构，使其微观结构更致密、强度更高。本研究旨在提高赤泥的综合利用水平，结果表明赤泥可以改善BMSC的力学性能，保护环境，同时降低BMSC的生产成本，创造良好的经济效益。
