Preparation and properties of a low-cost porous ceramic support from low-grade palygorskite clay and silicon-carbide with vanadium pentoxide additives

A low-cost porous ceramic support was prepared from low-grade palygorskite clay (LPGS) and silicon carbide (SiC) with vanadium pentoxide (V₂O₅) additives by a dry-press forming method and sintering. The effects of SiC–LPGS ratio, pressing pressure, carbon powder pore-forming agent and V₂O₅ sintering additives on the microstructure and performance of the supports were investigated. The addition of an appropriate amount of SiC to the LPGS can prevent excessive shrinkage of the support during sintering, and increase the mechanical strength and open porosity of the supports. The presence of SiC (34.4%) led to increases in the open porosity and mechanical strength of 40.43% ± 0.21% and (17.76 ± 0.51) MPa, respectively, after sintering at 700 °C for 3 h. Because of its low melting point, V₂O₅ can melt to liquid during sintering, which increases the mechanical strength of the supports and retains the porosity. Certainly, this can also encourage efficient use of the LPGS and avoid wasting resources.