Surface decoration of polyethylene terephthalate (PET) waste bottle-derived ultrafiltration membrane for enhanced lead ion removal and antifouling properties

PET waste bottle can be potentially used to create eco-friendly ultrafiltration (UF) membranes for water and wastewater treatment. The surface modification and functionalization of PET UF membrane offer opportunities to further heighten the performance of the membrane. In this study, phase inversion technique was used to fabricate PET UF membranes and PET/graphene oxide (GO) nanocomposite membranes through a facile GO suspension coating approach. The GO nanosheets were deposited on the PET UF membrane as a wavy and wrinkly layer. Using lead (Pb) ions and bovine serum albumin (BSA) feed solutions, the filtration performances of the neat PET and GO-PET membranes were evaluated. It was observed that, the Pb ions and BSA removal efficiencies were greatly enhanced by the surface decorated GO. Compared to neat PET, the 0.5GO-PET membrane exhibited improved flux performance by 188% and 61% for the removal of Pb ions and BSA, respectively. A high Pb ion removal of 100% and a BSA rejection of 97% were achieved by 0.5GO-PET membrane. The lower fouling tendency of 0.5GO-PET membrane during long-term filtration was attributed to the increased surface hydrophilicity and smoothness upon the deposition of GO layer. This study demonstrates a sustainable solution for efficient water treatment and heavy metal removal.