Preparation, characterization and applications of polyethersulfone/bentonite clay composite for protein removal

Abstract

In the current work, asymmetric polyethersulfone/bentonite clay nanocomposite (PES/BNT) membranes with differing clay dosages were successfully prepared by the phase inversion method aimed at protein separation. Means of characterization tools were harnessed to validate the fabrication process. The morphology and structure of membranes were examined by scanning electron microscope (SEM) and Fourier-transform infrared spectroscopy (FTIR) while additional surface properties such as pore size, porosity and hydrophilicity measurements were assessed. The permeability-selectivity trade-off of the membranes were assessed to probe the influence of additive content on the ultimate membrane functionality. The results indicated that best membrane performance was achieved with a BNT content of 0.225 g, resulting in enhanced dispersibility within the polymeric matrix. Besides, the inclusion of clay additive led to an increase in pore size ratio in the skin layer, further improving membrane permeability. The optimal membrane exhibited a permeate flux of 20.5 kg.m−2.h−1, while rejected 93 % of bovine serum albumin (BSA). Meanwhile, porosity, pore size and the contact angle measurements have recorded 71.8 %, 22.6 nm and 40.53°, respectively. These findings suggested that the PES/BNT membrane's permeation and separation characteristics, rendering them a viable option for a wide range of water and wastewater treatment applications.