Sol-gel derived zirconia membrane on silicon carbide substrate

Abstract

To enhance the high temperature and chemical corrosion resistances of ceramics membrane, a ZrO2/SiC ceramic membrane was prepared through sol-gel route followed by the dip-coating technique. The substrate layer was made of pure silicon carbide phase by evaporation-condensation process, and the separation layer was made of zirconia phase by solid-phase sintering process. The substrate layer was sintered at 2200 ℃ in the vacuum, and the pores were distributed in a narrow size range from 4.5–6.0 μm. When the membrane was sintered at 700 ℃, a defect-free separation layer formed on the substrate. With the increase of sintering temperature, the average pore size of the separation layer declined from 63 to 48 nm, and the water permeability declined from 355 to 273 L/(m2·h·bar). Our results indicate the ZrO2/SiC ceramic membrane has potential applications in the separation of high temperature or chemically corrosive wastewaters.