Fabrication of high-performance SiC ceramic membranes modified using in situ grown mullite whiskers and high-temperature filtration
The gas permeance and particle removal efficiency of silicon carbide (SiC) membranes are the most important performance indicators for high-temperature gas filtration. The rational design of SiC membrane microstructure has a positive impact on the improvement of performance indicators. This work prepared SiC membranes modified by in situ grown mullite whiskers, optimized their preparation conditions and investigated their performance improvement. The membrane suspension composition and sintering temperature were optimized using Taguchi’s method and gas permeance as the target. The thickness of the membrane was regulated by adjusting the spraying cycles and solid content in membrane suspension. Results showed that best membrane performance was obtained when the content of sintering aids, MoO 3, and AlF 3 ·3H 2 O were 8, 12, and 12 wt%, respectively; the solid concentration in membrane suspension was 30 wt%; the number of spraying cycles was 2, and the temperature was 1350 °C. The resulting membrane obtained a pore size of 5.8 µm and the Darcy's permeability coefficient k was 8.58 × 10 −12 m 2 . It also had good interfacial adhesion and thermal shock and corrosion resistances. The membrane achieved a PM 2.5 removal rate of more than 99.9 % at room temperature and high temperatures (100 °C–400 °C) with a low pressure drop below 1.4 kPa. Overall, the SiC ceramic membranes are prospective candidates for dust-laden gas filtration at high temperatures.
危险品化学品经营许可证（带存储）