The efficacy of membrane materials used to separate oil-water emulsions is limited by fouling mechanisms. This performance barrier is eliminated in a highly permeable, fouling-resistant membrane engineered at Kobe University, Japan.

A 10 nm thick silica layer is applied on the top surface of a porous polyketone membrane by means of electrostatic attraction. The combination forms an ultrathin, super hydrophilic material that demonstrates an almost 100% rejection against various oily emulsions.

Tests confirmed superior antifouling properties against oily emulsions containing pollutants such as proteins, surfactants, and other natural organic materials, and the membrane proved durable in acidic, alkaline, solvent and salt solutions. High water penetration was achieved without high pressure conditions, and water permeation was observed to be induced by gravity.

A membrane of 1m2 area is expected to effectively treat 6,000 liters of oily wastewater in one hour under 1 atm applied pressure.