Improvement of fouling resistance and mechanical reinforcement of polyacrylonitrile membranes by amino-functionalized multiwalled carbon nanotubes for membrane bioreactors applications

摘要

The goal of the current research is to simultaneously improve the fouling resistance and mechanical properties of polyacrylonitrile ultrafiltration membrane for membrane bioreactors (MBR) applications by a relatively easy method. For this purpose, amino-functionalized carbon nanotubes (NH2-MWCNTs) were employed, which have exceptional mechanical properties, hydrophilic functions, and good interaction with polyacrylonitrile. It was used to fabricate nanocomposite membranes with different MWCNTs contents. The rheological and thermodynamical aspects of the phase separation process were investigated to understand the mechanism of the membrane formation. The related characteristics including morphological, mechanical, and chemical properties of the membrane as well as its performance were studied. In the end, the synthesized membranes were used in an MBR setup for further investigations. The Pure water flux data shows considerable improvement from 810 LMH for the neat membrane to 1055 LMH for the 0.3 wt NH2-MWCNTs nanocomposite membrane. Mechanical enhancement was confirmed with about a 24 increase in the tensile strength and 61 for elongation at break. The membrane with 0.3 wt NH2-MWCNTs revealed the best porosity, fouling resistance, and performance in MBR with 95 flux recovery ratio and 64 improvement in permeated flux compared to the neat membrane.