Influence of process variables on properties of ceramic foams from tungsten tailings

The use of tailings for the preparation of ceramic foams is considered a safe and effective method for disposing of them. However, it is unclear whether wolframite tailings (WT) and scheelite tailings (ST) can synergistically be used to prepare ceramic foams, and the foaming process remains unclear. This study investigated the properties of ceramic foams prepared from these tungsten tailings at different ST contents, calcination temperatures, holding times, and SiC additions. The study found that the ceramic foams exhibited appropriate properties when the ratio of WT to ST was 6.5:3.5, with a bulk density of 0.823 g/cm3, a compressive strength of 1.557 MPa, an apparent porosity of 48.433 %, and a water absorption ratio of 58.477 %, which is expected to be used as a new type of material to replace the traditional material. Furthermore, changes in calcination temperature, holding time, and SiC addition significantly affected the properties. As these variables increased, the bulk density and compressive strength of ceramic foams gradually decreased, while the apparent porosity and water absorption ratio initially increased before subsequently decreasing. Further analysis indicated that the samples underwent oxidation reactions prior to the decomposition of CaCO3 and CaF2. These findings offered valuable insights into the comprehensive utilization of tungsten tailings and the low-cost preparation of ceramic foams for industrial applications.