Electrospinning silica aerogel electret doped polyimide membrane to prepare heat-resistant air filters for high-temperature PM capture

The rapid development of industry brings high-temperature polluting gases, which endanger the environment and human health. Therefore, achieving efficient gas filtration in a high-temperature environment is crucial. Silica aerogel was doped to fabricate polyimide (PI) nanofiber membranes by electrospinning for high-temperature resistance and high-efficiency filtration. The addition of silica aerogel retains the original excellent properties of the polyimide nanofiber membranes and increases the nanofiber surface area and the charge amount loaded on the surface. The filter efficiency of the prepared nanofiber membrane can reach 99.89 % for PM 0.3 at the gas flow rate of 35 L/min, and the corresponding pressure drop is only 52 Pa with a mass quality factor of 0.131. More importantly, the nanofiber membrane displays good filtration efficiency above 98 % at 300 °C for an extended period, which benefitted from the high-temperature resistant of polyimide and silica aerogel. Therefore, this work has great potential for high-temperature and high-efficiency air filtration.