Preparation and characterization of novel spontaneous foam ceramics based on all-solid waste

Foam ceramics were prepared through spontaneous foaming behavior using silicomanganese slag and desulfurization gypsum as raw materials. The effects of desulfurization gypsum content and firing temperature on foam ceramics' pore morphology and physical properties were investigated. The phases and microstructure of the samples were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and comprehensive thermal analysis (TG-DSC). The results showed that increasing the desulfurized gypsum content is beneficial for promoting the formation of a liquid phase and a uniform pore structure. The prepared ceramics exhibited low density (0.54 g/cm3), high porosity (80.56%), and compressive strength (5.85 MPa). Analyzing the toxic leaching behavior of heavy metal ions in the samples confirmed that all samples were safe and harmless. Furthermore, it was demonstrated through the self-foaming mechanism that desulfurization gypsum could be employed as a new type of spontaneous foam solid waste. This study provides an effective method for the synergistic preparation of foamed ceramics using silicomanganese slag and desulfurization gypsum. The utilization of solid waste in foamed ceramic production not only addresses the issue of significant waste accumulation but also offers economic benefits.