This work investigated the immobilization of municipal solid waste incineration (MSWI) fly ash using spent caustic as alkaline activator and blast furnace slag (BFS) as an additive, in which comparable alkalinity NaOH solution was used as controlling alkaline activator. The leaching behavior of heavy metals and organics in alkali-activated MSWI fly ash-based mortars were characterized by HJ/T 300–2007 method, BCR chemical speciation analysis, and total organics carbon (TOC) and organics measurements. It was found that the spent caustic-activated mortars exhibited a weaker immobilization performance for Cu, Pb, Zn and Cd, and a better performance for Cr (VI), comparing to NaOH-activated mortars. The presence of organics and the formation of ettringite in spent caustic-activated mortars made the immobilization of Cr(VI) more feasible. As increasing the BFS dosage, the immobilization efficiency of heavy metals was improved. For the immobilization of organics, the spent caustic-activated mortars were of a medium performance. This study extends a novel waste-derived alkaline activator in the alkaline activation filed and would favor the development of waste management.

这项工作研究了使用废碱作为碱性活化剂和高炉矿渣（BFS）作为添加剂固定化城市固体垃圾焚烧（MSWI）粉煤灰的方法，其中可比较的碱度NaOH溶液用作控制碱性活化剂。用HJ / T 300-2007方法，BCR化学形态分析以及总有机碳（TOC）和有机物测量来表征碱活化MSWI粉煤灰基砂浆中重金属和有机物的浸出行为。发现与NaOH活化砂浆相比，用过的苛性碱活化的砂浆对Cu，Pb，Zn和Cd的固定性能较弱，对Cr（VI）的固化性能更好。废碱活化砂浆中有机物的存在和钙矾石的形成使Cr（VI）的固定化更为可行。随着BFS剂量的增加，重金属的固定效率得到提高。对于固定有机物，用过的苛性碱活化的砂浆具有中等性能。这项研究在碱性活化领域扩展了一种新型的废物源碱性活化剂，将有利于废物管理的发展。