Preparation of nanoclay embedded polymeric membranes for the filtration of natural organic matter (NOM) in a circular crossflow filtration system

Abstract

In-house and commercial membranes were used with different properties for humic acid separation in a circular crossflow filtration system to determine the membranes’ performances. The in-house membranes were fabricated with the addition of bentonite nanoclay in Mendall, polyvinylidenefluoride (PVDF), polyphenylsulfone (PPSU), polysulfone (PSF) and polyether sulfone (PES) polymers. Bentonite nanoclay is recognized as a promising material for membrane applications due to its ability to produce membranes with superior properties such as the mechanical strength, large surface areas, adsorbing, antifouling and well-defined pore morphology. Three types of commercial membranes were also used for humic acid removal from water. The morphology, surface roughness, porosity and average pore size of the in-house and commercial membranes were then compared. The XM50 commercial membranes showed smooth and even surface topography as compared to other commercial and in-house membranes. The addition of bentonite into the polymer changed the morphological structure, surface roughness, pore size of the polymeric membranes. Pure water flux, permeate flux and rejection of humic acid were compared for in-house polymeric membranes and commercial membranes in a circular crossflow filtration system. It was observed that the fouling of humic acid was reduced by the addition of bentonite nanoclay in the in-house polymeric membranes.