Hot‐Pressed Polypropylene (PP) Membranes Modified With SiO₂ Nanoparticles for Advanced Emulsified Oil/Water Separation

ABSTRACT The separation of oil from water, particularly from emulsions, is a critical environmental challenge. Polypropylene (PP), despite its potential as a membrane material for this purpose, faces limitations due to the large pore size of nonwoven fabrics, which hinders its effectiveness in oil/water separation. This study presents an innovative and cost‐effective approach to enhance PP membranes for emulsified oil/water separation through a combination of hot pressing and surface modification using dopamine (DA) and SiO 2 nanoparticles. The resulting PP‐DA‐SiO 2 membranes demonstrate improved hydrophilicity, with a water contact angle reduced to 26.6° compared to the 133° of the unmodified PP membrane. Moreover, these membranes exhibit exceptional separation performance, achieving a peak emulsion flux of 1382 L · m −2 · h −1 and maintaining a separation efficiency above 98% under gravity. The tensile strength of the modified membrane is also significantly improved, increasing from 2.31 N to 9.01 N. The membrane's antifouling capabilities are also noteworthy, as it retains an emulsion flux of 1032 L · m −2 · h −1 with a 98% separation efficiency after five consecutive cycles. The membrane demonstrates exceptional chemical and mechanical stability following treatments with salt, pH solutions, and rubbing, underscoring its robustness and reliability in various environmental conditions. This work offers a practical and efficient method for fabricating high‐performance oil/water separation membranes, advancing the application potential of PP in environmental remediation technologies.