Impacts of Heat Treatment Medium on Performance of Aliphatic-aromatic and Aromatic-aromatic based Thin-film composite (TFC) polyamide Reverse Osmosis (RO) Membrane

In this study, we report the impact of heat treatment medium (hot air, hot water & steam) 'on structure and performance of aliphatic-aromatic and aromatic-aromatic types thin-film composite (TFC) polyamide reverse osmosis (RO) membranes prepared by in-situ interfacial polymerization. Aliphatic-aromatic polyamide membranes were prepared using polyethylene' imine (PEI) & isophthaloyl chloride (IPC) and aromatic-aromatic polyamide membranes were prepared using m-phenylene diamine (MPD) & trimesoyl chloride (TMC). Thin film coating of polyamide was given over laboratory synthesized microporous polysulfone supports. TFC membranes prepared using three different heat treatment media were characterized in terms of water permeability, separation of NaCl solute, water contact angle and atomic force microscopy studies. It was found that different heat treatment media produced. TFC polyamide membranes with widely varying water fluxes, salt rejections, and surface properties under identical coating conditions and it has different impacts on aliphatic-aromatic and aromatic-aromatic type polyamide composite membrane performances. The surface hydrophilicity of the steam and hot water-cured membranes increased more than that of hot air cured membranes for aromatic-aromatic type TFC-RO membrane. Heat treatment in hot water and steam media results TFC membrane with the more permeates flux and salt rejection for both aliphatic-aromatic and aromatic-aromatic type.