Carboxylate and hydroxylate MWCNT/PES mixed matrix membrane with higher hydrophilicity and antifouling capacities for oily wastewater treatment
Paper ID : 1222-MST2015-FULL
Authors:
1Seyyed Mehdi Abedan Dehkordi *, 1Farzin Zokaee Ashtiani, 2Amir Fouladitajar, 3Ali Etemadzadeh
1Amirkabir University of Technology
2Amirkabir University of technology
3Amirkabir University
Abstract:
Membrane filtration is a promising technology for oily wastewater treatments considering its high separation efficiency along with simplicity and fairly short process time. However, the application of this technology has been limited by severe fouling caused by oil droplets in the oily wastewaters resulted in less permeability and flux. In this study, the pure polyethersulfone membrane was fabricated and modified by two different functionalized multi-walled carbon nanotube, Carboxylated MWCN and Hydroxylated MWCN, to increase its hydrophilicity and oil resistant. Carboxylated MWCN/Polyethersulfone and Hydroxylated MWCN/Polyethersulfone mixed matrix microfiltration membranes were manufactured via phase inversion method (immersion precipitation). Nanocomposite/polymer solutions for membrane formation were prepared in NMP with 16 wt% PES and 1 wt% PVP with respect to the total volume of solution. The functionalized MWCNTs were added to the casting solution in different concentrations (0.05, 0.1, 0.15 and 0.2wt% based on the polymer constituents) and homogenously dispersed by sonication stirrer for 20min. The effect of these functionalized multi-walled carbon nanotubes on the performance and antifouling properties of polymeric membrane permeability in oily water separation was investigated in terms of oil water flux via cross-flow flat sheet module at 2 atmosphere pressure. The results indicated that the antifouling capacity of the membrane was enhanced by blending functionalized MWCNTs to the casting solution. Carboxylated MWCNT has a better modifying effect on the membrane permeability and increases the oil/water flux by 80 percent, however the hydroxylated MWCN increases the flux by only 50 percent. Comparison of the flux in different concentration of MWCN also shows that membrane has the best permeability at the 0.1% of Carboxylated MWCN and 0.15% of Hydroxylated MWCN and higher concentration of MWCNT has a reverse effect on the permeability and decrease the flux due to the aggregation of the nanoparticles in the membrane matrix.
Keywords:
PES membrane, Carboxylated MWCNT, Hydroxylated MWCNT, Fouling capacity, Oily water
Status : Paper Accepted (Oral Presentation)