Solvent resistant nanofiltration: developing understanding of transport mechanisms

In recent years the possibility of using polymeric nanofiltration (NF) membranes for non-aqueous separations has been explored. There is, however, significant debate concerning fundamental mechanisms where concepts include solution-diffusion and ‘pore’ flow. This paper presents nanofiltration and swelling data for polyacrylonitrile (PAN)/poly-dimethylsiloxane (PDMS) composite membranes with a range of low and higher polarity solvents, some of which contained solutes in the range 84-612 MW. The influences of parameters such as crossflow rate, applied pressure, solute size and solvent polarity on filtration performance are presented and measures of flux and solute rejection are related to membrane swelling. More comprehensive descriptions of the experimental apparati and results are shown in [1-7].