Electrospun meta-aramid/polysulfone-amide nanocomposite membranes for the filtration of industrial PM2.5 particles

Filtering of industrial PM2.5 is a major challenge for global environmental and animal protection. Filtering of materials with excellent thermal stability and other comprehensive performances is required for the removal of fine particles in high-temperature operating industries such as steel, cement, metallurgy, incineration, etc. In this study, a meta-aramid/polysulfone-amide (PMIA/PSA) composite nanofibrous filtration membrane is prepared via solution electrospinning for the development of high-temperature-resistant filtering products. To maximize the merits of each component, PMIA/PSA composite nanofibrous membranes with different mass blending ratios are prepared to determine the optimal balance. It is found that the PMIA/PSA composite nanofibrous membranes show excellent thermal stability and thermal shrinkage performance. They also maintain superb mechanical retention ratios after 200 h treatment at 200 °C. In addition, they exhibit excellent removal efficiency of polystyrene aerosol (PSL) particles of various sizes. It is found that the removal efficiency of PMIA/PSA (3/7) is 96.7% for 0.1 μm, 98.3% for 0.2 μm and 99.6% for 0.3 μm particles and it possesses optimal filtration resistance (79 Pa), while other composite membranes can reach a removal efficiency of over 99.7%. Our experimental results illustrate that the filtration efficiency for PM2.5 of PMIA/PSA (7/3), (5/5) composite nanofibrous membranes is still kept as high as 99.9% even after being treated at 200 °C for 120 h. It indicates that the prepared composite nanofibrous membranes have potential for applications where high-efficiency filtration is desired, such as bag dust filters for use under high temperatures.