Researchers at Kobe University have developed an ultrathin membrane with a resistant silica surface treatment that enables outstanding separation of oil from water. The membrane's ability to separate water from a wide range of oily materials marks a groundbreaking achievement in separation science. The results were published in the Journal of Materials Chemistry A.
Oil and water separation technology is critical for solving issues related to oil spills and water pollution. With the predicted amount of clean global water reaching unnerving levels, separation technologies that focus on water and oil separation are becoming increasingly more important. Membrane separation offers a cost-effective and energy-efficient alternative to centrifugation and chemical coagulation. However, fouling issues, where oil droplets are irreversibly absorbed on the surface of the membrane, have been a substantial barrier for membrane research and development.
Researchers have now developed a membrane consisting of a porous polyketone support with a 10-nanometer thick silica layer at the top surface. The silica layer was generated onto the PK fibrils using electrostatic attraction- the negatively charged silica was attracted to the positively charged PK. The PK membrane has a high water permeance as a result of the large pores and high porosity. The silicification process provided a strong oil-repellant coating to protect the surface modified membrane from subsequent fouling problems.