A new and economic approach to fabricate resistant porous membrane supports using kaolin and CaCO3

This new and economic approach to fabricate resistant porous membrane supports consists of Algerian kaolin and calcite (CaCO3) instead of Al2O3. The porous mullite (3Al2O3·2SiO2) and anorthite (CaO·Al2O3·2SiO2) based ceramics were obtained by solid state reaction. Different calcite amounts (10–28 wt%) have been added into kaolin halloysite type (Al2O3·2SiO2·4H2O) in order to control pores forming with appropriate distribution and sizes. Based on a pore distribution and formed phases, a kaolin + 15 wt% calcite (K15C) mixture was selected for flat and tubular configurations. A porosity of 45–52% was also obtained when K15C compacts were sintered at 1100–1250 °C. For example, porosity, average pore size (APS) and 3 point flexural strength were 49%, 3 μm and 87 MPa (same as Al2O3 value), respectively when K15C compacts were sintered at 1250 °C for 1 h. Finally, a correlation between microstructure and mechanical properties of elaborated supports has been discussed.