Synthesis and Application of Functionalized Carbon Nanotube Infused Polymer Membrane (fCNT/PSF/PVA) for Treatment of Phenol-Containing Wastewater

In this study, polymer composite membranes comprising carbon nanotube (CNT), polysulfone (PSF) and polyvinyl alcohol (PVA) were synthesized via the phase inversion method and used to remove phenol from the phenol-containing wastewater. The fabricated membranes were reinforced with the functionalized carbon nanotubes (fCNTs) and coated with PVA to enhance their mechanical strength and anti-fouling property, respectively. Performance of the membranes was evaluated for the treatment of the synthetic phenol-containing wastewater using a dead-end filtration cell operated at different feed pressures in the range of 1-8 bar. The non-coated membrane with 5% fCNTs displayed the highest flux of 70.21 L.m2.h-1, followed by the PVA coated membrane loaded with 5% fCNTs displaying flux of 59.63 L.m2.h-1. The results showed that the non-coated PSF membrane loaded with 5% CNTs displayed the highest permeability of 28.24 L.m-2.h-1.bar-1 at transmembrane pressure (TMP) of 1 bar. Pure PSF with 0% loaded fCNTs showed the lowest permeability of 0.68 L.m-2.h-1.bar-1 at TMP of 1 bar. Analysis of the constituents of the wastewater using a pre-calibrated Gas chromatography-Mass chromatography (GC-MS) reveal that the membrane reinforced with fCNTs (1% CNT loading) and coated with PVA displayed the highest phenol rejection of 65%. It is noteworthy to mention that all the membranes showed 100% selectivity to the hydrocarbons (petrol and kerosene) contained in the wastewater. The results of this study could be a platform to develop cost-effective membrane materials for treatment of the refinery wastewater at low pressure for low energy consumption.