Carbon Nanotube Enhanced Filtration and Dewatering of Kerosene

Abstract

Current approaches to dewatering aviation fuel such as kerosene are adsorption by activated charcoal, gravity separation, etc. The objective of this work is to develop and demonstrate the filtration and dewatering of kerosene using a carbon nanotube immobilised membrane (CNIM). Highly hydrophobic membranes were prepared by immobilising carbon nanotube (CNTs) over polytetrafluoroethylene (PTFE) and polyvinylidene difluoride (PVDF) microfiltration membrane for the dewatering of ppm level water from kerosene. The effects of different CNT concentrations on membrane morphology, hydrophobicity, porosity, and permeability were characterised. After immobilising CNT into membranes, the contact angle increased by 9%, 16%, and 43% compared to unmodified 0.1 μm PTFE, 0.22 μm PTFE and 0.22 μm PVDF membranes, respectively. The CNIM showed remarkable separation efficiency for the fuel-water system. The micro/nano water droplets coalesced on the CNT surface to form larger diameters of water droplets detached from the membrane surface, leading to enhanced water rejection. In general, the water rejection increased with the amount of CNT immobilised while the effective surface porosity over pore length and flux decreased. PTFE base membrane showed better performance compared to the PVDF substrate. The CNIMs were fabricated with 0.1 and 0.22 μm PTFE at an optimised CNT loading of 3 and 6 wt.%, and the water rejection was 99.97% and 97.27%, respectively, while the kerosene fluxes were 43.22 kg/m2·h and 55.44 kg/m2·h respectively.

Omniphobic, Bilayer Carbon Nanotube-Immobilized Fluorinated (FAS) Membranes for Bioethanol Recovery at High Concentrations via Membrane Distillation

“…All three of these peaks are characteristic features of the CNTs and are observed in both samples. 64 Thermogravimetric analysis (TGA) was performed for the modified and unmodified samples using the PerkinElmer Pyris 7 TGA system 24,45,46,49 and is displayed in Figure S3. Thermogravimetric analysis (TGA) was performed to study the thermal stability of modified and unmodified samples.…”

“…33,34,66,67 Meanwhile the ethanol vapor passed through the membrane via activated diffusion over the CNT surface. 45,46 Here, the carbon nanotubes acted as a sorption site for the vapor molecules, particularly ethanol. 15,16,22,68−73 The temperature difference between the feed and permeate side acts as the driving force for the molecules to overcome diffusional resistance.…”

“…74,75 CNTs are particularly well-suited for creating a micro/nanometer-level rough hierarchical surface 42,65 and the fluorination on the CNT-coated surface strengthened the re-entrant structures. 45,46,51 Due to the formation of these multiscale textures in FAS-CNIM, high surface roughness and contact angles were also observed which contributes a stable omniphobicity and antiwetting resistance. 51…”

Enhanced Recovery of Aviation Biofuel Precursor Isoprenol Using Nanocarbon-Immobilized Membrane-Based Membrane Distillation

“…The membrane is one of the most critical components in MD, since it has a direct impact on separation efficiency. , In organic recovery via MD, the membrane–solvent interaction plays an important role in permeation rate through membrane pores. Several modification methods have been reported to increase the partition coefficient of specific solvents through the membrane. − We have used several nanocarbon morphologies in our membranes, including carbon nanotubes (CNTs), functionalized carbon nanotubes (f-CNTs), graphene oxide (GO), and reduced graphene oxide (r-GO). − These have resulted in significant improvements in active diffusional transport as well as increased flux, selectivity, and mass transfer coefficients. − We have also shown that integrating air sparging during sweep gas MD (AS–SGMD) synergistically enhances separation performance while contributing to improved antifouling behavior. , Air sparging is known to change the organic compound’s behavior at different temperatures, especially for high boiling solvents, and several studies have shown the removal of organics via air stripping at lower temperatures. − The objective of this study was to investigate the potential of AS–SGMD in the enrichment of low-concentration aqueous isoprenol using different nanocarbon-immobilized membranes.…”

Synergistic Antiviral Effects of Metal Oxides and Carbon Nanotubes

“…Besides M-NPs and MO-NPs, nanocarbons [ 21 , 22 , 23 ] such as carbon nanotubes (CNTs) have also been used as antimicrobial agents [ 20 , 22 ]. CNTs are allotropes of carbon with great hydrophobicity and have been used in various other fields such as solvent enrichment [ 24 , 25 , 26 , 27 , 28 ], fouling reduction [ 29 , 30 ] and hydrocarbon dewatering [ 31 , 32 ]. Extensive research has been performed on CNTs to explore their antimicrobial properties [ 33 , 34 ].…”