Municipal solid waste incineration (MSWI) fly ash is solid waste containing heavy metals and needs to be safely disposed of. This study investigated the feasibility of alkali-activated technology for solidification/stabilization (S/S) MSWI fly ash via sodium-montmorillonite (MT) as an alkali-activated cementitious material. MT was added (0–20 wt%) to explore its effects on the compressive strength, leaching concentration, and chemical speciation distribution of heavy metals in solidified bodies. Additionally, several tests including XRD, FTIR, MIP, and SEM of solidified bodies without and with MT were analyzed. Results showed that compared to the blank specimens, the compressive strength of solidified bodies increased by 56%–159% and 8.4%–35.8% at curing times of 3 days and 28 days, respectively. In the case of 10 wt% MT specimens, the leaching concentration of heavy metals was the lowest, which met the Chinese standard (GB16889-2008). Chemical speciation of heavy metals, XRD, FTIR, MIP, and SEM analysis indicated that the mechanism of S/S heavy metals in solidified bodies was mainly through co-processing methods of physical and chemical.

城市固体废物焚烧 (MSWI) 飞灰是含有重金属的固体废物，需要安全处置。本研究调查了碱激活技术通过钠蒙脱石 (MT) 作为碱激活胶凝材料固化/稳定 (S/S) 垃圾焚烧飞灰的可行性。添加 MT（0–20 wt%）以探索其对凝固体中重金属的抗压强度、浸出浓度和化学形态分布的影响。此外，还分析了几个测试，包括 XRD、FTIR、MIP 和 SEM 的固化体，没有和有 MT。结果表明，与空白试件相比，固化时间为 3 天和 28 天时，固化体的抗压强度分别提高了 56%~159% 和 8.4%~35.8%。在 10 wt% MT 样本的情况下，重金属浸出浓度最低，符合国家标准（GB16889-2008）。重金属化学形态分析、XRD、FTIR、MIP、SEM分析表明，S/S重金属在凝固体中的作用机理主要是物理化学协同处理方法。