Surface modification of polymeric flat sheet membranes by adding oligomeric fluoroalcohol

Abstract

Abstract The present study attempted to modify the surface of polymeric membranes by mixing 2-(perfluoroalkyl)ethanol with polyethersulfone to improve the hydrophobicity of the membrane. The characteristics of the surface-modified membrane were examined by using the contact angle, liquid entry pressure (LEPw), X-ray photoelectron spectroscopy spectra, and scanning electron microscopy measurements. The modified membrane was tested for SO2 absorption. The surface contact angle and LEPw values increased by the addition of fluoroalcohol. The fluorine/carbon atomic ratio decreased with increasing evaporation period. The modified membrane was utilized for the absorption of SO2 from the simulated flue gas in alkaline medium (0.5 m NaOH solution). The SO2 removal efficiency slightly decreased probably due to the transformation of the finger-like structure into a sponge-like structure, and the increase in the membrane resistance. The SO2 absorption rate also increased as the gas flow rate increased.