Self-support thin film nanofibrous composites ultrafiltration membrane based on PET waste flake for oil/water separation

Abstract

Commercial ultrafiltration (UF) membranes are typically produced with the phase inversion method. Higher density and torturous pore channels of these membranes, result declined water flux rate. This research looks to develop a new class of thin film composite (TFC) UF membranes with high flux, based on nanofibrous support with a thin film top layer. For this, in the first step, the PET electrospun nanofibrous sub-layer with thicker fiber diameter was prepared from PET waste flake, and in the next step, the PET nanofibrous mid-layer with thinner fiber diameter (compared to first sub-layer fiber diameter) was prepared with electrospinning on the first sub-layer. Finally, a hydrophilic top layer based on chitosan/multi-walled carbon nanotube was applied on the self-support PET/PET nanofibrous support with the dip-coating method. The result showed that prepared membranes had high pure water flux (240 l/m2 h bar), oil/water emulsion steady flux (60 l/m2 h bar), and oil emulsion retention (~ 99.9%). Finally, the filtration performance of PET/PET UF and other nanofibrous and commercial UF membranes was evaluated.