Preparation and characterization of high flux alumina membrane supports by composite pore former method

Abstract Pore formers are essential for preparation of high performance ceramic membrane supports. The removal of the pore former is a key process affecting the sintering rate and quality. To avoid excessive concentration of pore former removal at a certain temperature, we choose carbon black, sawdust and hydroxyethyl cellulose (HEC) as a composite pore former to prepare supports with high flux and sinter the supports rapidly. According to thermal analysis results of the three pore formers, we designed the ratio of sawdust/carbon black/HEC as 5/3/2. By tuning the firing temperature, pore former content and heating rate, the supports prepared with this method exhibited a pure water flux of 45.4 m3m−2h−1bar−1 and a bending strength of 46.2 MPa. The properties are highly dependent on the pore former content and slightly on the heating rate, which means that the composite pore former method can greatly reduce the time consumption without damage to the support quality. The corrosion experimental results also indicate the supports are quite resistant to strong acid and alkali corrosion. In summary, the composite pore former method is a promising way to fabricate supports with excellent performances and realize the fast firing of high porosity ceramic membrane supports.