Separation Characteristics of Surface Modified Polysulfone Ultrafiltration Membrane using Oxidative Catalytic Polymerization of Aniline

Abstract

The commercially available Polysulfone (PSF) membrane surface was modified by solution polymerization of aniline using different oxidation catalysts i.e., FeCl3, CuCl2, and APS. Modified membranes were then characterized with respect to physio-chemical properties like surface chemistry, porosity, wettability, surface roughness, morphology, etc. It was observed that the hydrophilicity/ wettability of membranes was increased upon surface modification by polyaniline which again depended on the nature of the oxidation catalyst used. Membranes developed using FeCl3 and CuCl2 as oxidants exhibit improved permeation, protein rejection, and antifouling properties, whereas decrement was observed in modified membrane performance using APS as an oxidant. Among all modified membranes, PSF/PANI-CuCl2 membrane demonstrates the most promising performance in terms of higher pure water flux and protein solution permeation flux i.e., 453.3 L/m2.h and 122.3 L/m2.h respectively. The PSF/PANI-CuCl2 membrane unveils superior resistance towards bio-fouling in comparison to the other modified membranes. Analytical techniques were used for the characterization of the modified membranes such as ATR, XPS, FESEM, and AFM. Contact angle measurement also supports the fact that PSF/PANI-CuCl2 membrane has a better chemical and physiological attachment to the polysulfone membrane surface.