Sintering temperature dependence of low-cost, low-density ceramic proppant with high breakage resistance

Abstract The low-cost, low-density ceramic proppants with high breakage resistance were successfully prepared from low-grade bauxite (59.9 wt%Al 2 O 3 ) partially replaced by purple sand via solid state sintering method. The phase evolution and microstructure of the ceramic proppants sintered at different temperatures were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that with the increase of sintering temperature, the crystalline phases were transferred from sillimanite to mullite and corundum, and glass phase was generated. When sintered at the proper temperature of 1440 °C, the close integration of mullite and corundum bonded by the proper liquid phase was observed, and the obtained proppant presents the apparent density of 2.98 g/cm 3 , bulk density of 1.64 g/cm 3 and lowest breakage ratio of 7.8% under 52 MPa closed pressure.