Modified Magnesium Oxysulfate Foam Cement Doped with Iron Tailings

The enhancement of the utilization rate of solid waste, along with balancing the comprehensive performance of materials, presents a significant challenge in the development of new functional building materials. This study examined the effects of high concentrations of iron tailing powder on the crystallization characteristics, pore structure, compressive strength, and water absorption of modified magnesium oxysulfate (MOS) foam cement with different dry densities. Furthermore, employing chemical foaming technology, the study characterized and analyzed the microstructure of modified MOS foam cement hydration products through scanning electron microscopy (SEM) and X-ray diffraction analysis (XRD). The results indicated that the addition of an acidic modifier effectively facilitated the hydration reaction in the MgO-MgSO₄-H₂O system, enhancing the micro-crystallization characteristics of MOS foam cement. The internal pores were uniformly round, with a dense crystal structure within the pore walls. The compressive strength of the material with 40% dry density A08 grade iron tailing powder reached 6.83 MPa, and the lowest water absorption was 5.32% at a dry density of A09.