Oxidation-bonded SiC membrane for microfiltration

Porous SiC is a proven viable material for microfiltration membranes, but its application has been limited by high fabrication cost. In this study, the oxidation bonding technique was used for the first time to fabricate SiC microfiltration membrane. The study was divided into two parts: optimization of the slurry used to dip coat the SiC particles over a porous SiC ceramic support and controlling the oxidation behaviour of SiC with respect to temperature. The oxidation behaviour during different thermal treatments was related to pore morphology and ultimately the membrane permeance. By coating the clay-bonded SiC support with oxidation-bonded SiC and sintering the coating at 1100 °C for 1 h, we prepared a defect-free microfiltration membrane with pure-water membrane permeance of >210 L m−2 h−1 bar−1, an average pore size of 93 nm, and a narrow pore-size distribution.