Characterization of novel acid-stable NF membranes before and after exposure to acid using ATR-FTIR, TEM and AFM Academic Article uri icon

abstract

  • The paper demonstrates the capabilities of a number of newly proposed techniques in analyzing the structural and morphological characteristics of the active layer of composite asymmetric membranes. The chemical stability of recently developed acid-stable nanofiltration membranes is analyzed in terms of the swelling, morphology and water vapor sorption. These characteristics are compared for pristine membranes and those exposed to hot 20% sulfuric acid solutions for various times. Swelling and morphological changes measured by atomic force microscopy (AFM) and transmission electron microscopy (TEM) indicate that swelling of the active layer gradually increases upon degradation, presumably due to disruption of the cross-links and/or generation of a larger number of hydrophilic groups. The change in swelling, which apparently proceeds in a uniform fashion …

publication date

  • January 1, 2005