Magnetically induced PSA composited CNT‐Fe3O4 ultrafiltration membrane

Based on the hydrophilicity of carboxylated carbon nanotubes (CNTs) and the paramagnetism of ferroferric oxide (Fe3O4), a CNT‐Fe3O4 nanocomplex was produced by in situ liquid phase synthesis and a magnetically induced polysulfone amide (PSA) composited CNT‐Fe3O4 ultrafiltration membrane was prepared using an immersion precipitation phase transformation with an inexpensive PSA fiber as the matrix. Fe3O4 nanoparticles were distributed evenly on the CNTs, and the obtained CNT‐Fe3O4 complex exhibited good magnetic properties. For the magnetically induced PSA composited CNT‐Fe3O4 ultrafiltration membrane, the water flux and retention rate under the magnetic field of 1450 Gs were 421.26 L/m2 h and 96.70%, respectively; porosity and pore size were 38.75% and 58.52 nm; contact angle was 39.48°; average tensile strength was 4.61 N/mm2; and weight retention rate reached 29.00% under heat treatment at 900°C. The water flux decreased by 5.40% and 39.33% after 3 weeks of acid and alkaline immersions, respectively. The inhibition zone diameter of Escherichia coli was 11 ± 0.24 mm, and that of Staphylococcus aureus was 11 ± 0.35 mm. The magnetically induced PSA composited CNT‐Fe3O4 ultrafiltration membrane demonstrated stronger electronegativity, smaller average roughness, higher flux recovery rate value, and lower irreversible flux recovery rate value.