The mass transport of components during the pervaporation of binary butanol aqueous solutions using commercial PDMS membranes has been investigated. A simplified approach of the Maxwell-Stefan model was extended to include the effect of membrane swelling and temperature on the diffusion coefficients and sorption properties. Partial permeate fluxes obtained at different temperatures and concentrations have been fitted to determine the extended model parameters. The sorption properties and diffusion coefficients of components have been estimated using fitted parameters. Predicted values of the solubility and diffusivity were used to calculate and compare the permeability of the components under different operating conditions.Abbreviations: HPLC - High performance liquid chromatography; MS - Maxwell-Stefan; PDMS - Polydimethylsiloxane; SEM - Scanning electron microscope