(152bm) Dewatering of Aviation Fuel: Development of Superhydrophobic Carbon Nanotube Immobilized Membranes

The presence of even a trace amount of water (ppm level) in aviation fuel such as Kerosene can lead to engine malfunction and consequently, there are very strict guidelines for this. The current approach to dewatering aviation fuel is adsorption on activated charcoal which is an expensive technique and has serious environmental ramifications because the spent charcoal is discarded as hazardous waste. The objective of this work was to develop a novel polymeric filtration medium for the dewatering of aviation fuel as well as hydrocarbon solvents. Super-hydrophobic membranes were prepared by immobilizing carbon nanotubes (CNTs) over polytetrafluoroethylene (PTFE) microfiltration membrane for the dewatering of ppm level water from organic-water mixtures. The carbon nanotube immobilized membrane (CNIM) showed remarkable separation efficiency for removing trace water from the fuel as well as solvents. The CNIMs contained less than 6% CNTs by weight and showed water rejection as high as 99.97% while the kerosene production was as high as 55.44 kg/m².hr. The micro/nano water droplets exist as stable colloids in the organic phase. The CNTs served as nucleation sites for the coalescence of these to form larger diameter droplets that could be removed by the hydrophobic filter. The effects of CNT concentrations on membrane morphology, hydrophobicity, porosity, and permeability were characterized and different solvents were also evaluated. These novel hydrophobic filters appear to be effective in the purification of fuels as well as organic solvents.