Synthesis and characterization of porous ceramics from spodumene tailings and waste glass wool

Glass wool waste remains a challenging waste fraction with relatively little utilization prospects. The present study investigated the development of porous ceramic materials from glass wool waste and spodumene tailings mainly made of quartz feldspar sand (QFS), with 0.05–0.5% silica carbide (SiC) as a pore-forming agent. The formulated compositions were sintered at 950 °C and analyzed in terms of mechanical properties, phase composition, and microstructure using X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray micro-computed tomography. The results showed that a synergetic effect of glass wool and SiC started to be significant from 15 wt% glass wool and 0.05 wt% SiC, the strength reducing and the porosity increasing with the increase of SiC. The porous ceramics were largely amorphous, with compressive strength ranging from 5 to 30 MPa while the water absorption and apparent density ranged from 2 to 10% and 0.7–1.2 g/cm3, respectively. The total porosity varied between 20 and 75%, and the wall thickness between 62 and 68 μm; besides, most of the prepared materials floated in water. These results are of interest for the repurposing of glass wool waste in the development of non-flammable lightweight materials for potential filtering or high-rise building applications.