Preparation and Performance of <scp>PVA</scp>–Benzoxazine Membranes for the Rejection of Some Heavy Metals via Pervaporation

ABSTRACT In the study, the rejection of some metals from synthetic and wastewater was carried out by the pervaporation method using poly(vinyl alcohol)/benzoxazine (PVA/Bz) membranes. For this purpose, monomeric or polymeric benzoxazines were first synthesized and characterized. Subsequently, PVA/benzoxazine membranes were prepared and their morphologies characterized. Afterward, the removal of selected heavy metals Cr(VI), Fe(II), Ni(II), Cd(II), Cu(II), and Mn(II) from wastewater and synthetic water was studied by the pervaporation method using PVA/benzoxazine membranes. The polymeric membranes (PVA/BBz) demonstrated efficacy in the rejection of Cr(VI), Fe(II), Ni(II), Cu(II), and Mn(II) in comparison to the monomeric membranes (PVA/PBz) for synthetic water. However, studies conducted with real wastewater also showed the same tendency as studies conducted with synthetic water. The highest separation factor observed was 827% rejection at a flux of 1.98 kg/m 2 .h in synthetic Ni(II) solution and 699% rejection at a flux of 1.13 kg/m 2 .h in a real wastewater for the PVA/BBz 1 membrane. This method offers a significant advantage by not only removing heavy metals from wastewater but also allowing the concentrated heavy metals in the feed solution to serve as a raw material source for various industrial sectors.