Superhydrophobic Solution Blow Spinning PTFE – SiO 2 Composite Membranes for Enhanced Liquid–Liquid Extraction

ABSTRACT An ultrafine‐fibrous polytetrafluoroethylene (PTFE)–SiO 2 membrane was successfully fabricated using the solution blow spinning (SBS) method. This membrane demonstrated superhydrophobicity (water contact angle > 150°) and oleophilicity (ethyl acetate contact angle = 0°) compared to a commercial PTFE membrane. Additionally, the SBS PTFE–SiO 2 membrane exhibited a high porosity of 83% compared to 55% in the commercial PTFE membrane. When used for membrane‐assisted extraction, the PTFE–SiO 2 membrane exhibited a higher caffeine transport rate (3.84 × 10 −7  m s −1 ) than the commercial PTFE membrane (2.18 × 10 −7  m s −1 ). The addition of SiO 2 nanoparticles provided better hydrophobicity and higher phase stability during membrane‐assisted solvent extraction. Given the excellent thermal and chemical stability of PTFE–SiO 2 , this type of membrane shows potential for high‐value solvent extraction and stable long‐term operation with no emulsion generation. The SBS method offers a promising alternative for the sustainable fabrication of PTFE membranes on a larger scale without the need for organic solvents or lubricants.