Transport of a Liquid Water-Methanol Mixture in a Single Wall Carbon Nanotube

Abstract

In this work, a molecular dynamics simulation of the transport of water - methanol mixture through the single wall carbon nanotube (SWCNT) is reported. Methanol and water are selected as fluid molecules since water represents a strongly polar molecule while methanol is as an intermediate between polar and strongly polar molecules. Some physical properties of the methanol-water mixture such as radial and axial density, hydrogen bonding, number of contacts and minimum distance between mixture and SWCNT molecules and also diffusivity of the mixture as a transport property were calculated during the simulation. Results showed that mixture of the selected molecules inside SWCNT have different properties during transport along the SWCNT in comparison with pure fluids inside SWCNT. Also methanol molecules diffuse faster than water molecules inside nanotube due to a weaker hydrogen bonding network. These differences among physical properties of the fluids inside SWCNT can be a key parameter for designing the new separation equipments and sensors using SWCNT.