Bio-based superhydrophilic foam membranes for sustainable oil–water separation

Abstract

The development of a low-cost, high-performance, biobased membrane technology has been attempted to treat environmentally sensitive wastewater streams. Novel foam membranes (FMs) were derived from agarose (Agr) and gelatin (Gel) in combination with a non-toxic fruit extract and natural crosslinker, genipin (G). FMs were successfully tested for their oil–water separation efficiencies. FMs attained unique capillary microstructures (10–45 μm) as a result of the controlled lyophilization process, which allows selective permeation of water. Stable microporous membranes with nominal pore sizes in between the microfiltration and ultrafiltration range generated as high as >500 L m⁻² h⁻¹ continuous flux with ∼98% pure product water. One of the advantages of these FMs is that after oil–water separation, they can undergo an easy membrane cleaning process, thereby retaining surface activity for long term performance.