Studies on Composite Polyphenylsulfone Membranes for Protein Rejection Applications

Abstract

Wastewater production is unavoidable because it is an inherent component of the value chain in all sectors of life. Faced with water constraints, the global community seeks to investigate all methods for decreasing the over exploitation of finite freshwater resources. Membrane technology has become the preferred approach for reclaiming water from various wastewater sources. Among commercially available polymeric membranes, polyphenylsulfone (PPSU)-based membranes play a vital role as they exhibit excellent thermal and mechanical stability, high chemical resistance, impact resistance and hydrolytic stability. However, PPSU-based membranes are hydrophobic, causing poor antifouling ability in aqueous phase separation urge polyphenylsulfone membrane for future development. This research work focused on modifications of polyphenylsulfone membranes by adding polymeric, inorganic and organic-inorganic additives to improve the physicochemical properties and their performances. The various additives employed in this study includes zwitterionic polymeric nanoparticles, polymeric microspheres, Ag-doped zinc oxide, PANI-bentonite nanocomposite, HKUST-1 metal-organic framework and AgI/UiO-66(NH2) metal-organic frameworks. All these additives are synthesized and are hydrophilic. The as-fabricated composite or nanocomposite membranes were completely characterized using analytical techniques. The PPSU membrane with 1.0 wt.% PANI-bentonite nanohybrid membrane showed the highest BSA rejection rate was 96.7% and egg albumin was 95.2% and HKUST-1 MOF of 1.0 wt.% membrane showed the highest pepsin rejection was 79.5%. The highest flux recovery ratio (FRR) was 85.2% showed by the 1.0 wt.% of polymeric microspheres incorporated membrane. The PPSU membrane with 1.0 wt.% of HKUST-1 showed the highest pure water permeability (198.12 Lm-2h-1bar-1). The 1.0 wt.% membrane showed the lowest contact angle and the highest hydrophilicity due to the addition of zwitterionic polymeric nanoparticles. All the as-synthesized composite additive materials not only increased hydrophilicity but also altered the membrane surface charge feasible for protein rejection.