MWCNT-tailored PVA membranes for enhanced dehydration of ethyl acetate-ethanol-water ternary mixture via pervaporation

Ethyl acetate, a highly relevant and eco-friendly industrial solvent used in various pharmaceutical, paint, and varnish industries, has seen an increase in demand in recent years. This study reinforced a PVA-based novel mixed matrix membrane with multi-walled carbon nanotubes (MWCNTs) due to their small dimensions and high surface area, to separate a ternary mixture of ethyl acetate, ethanol, and water by pervaporation. The synthesized membranes were thoroughly characterised for different nanofiller loadings, and the degree of swelling was assessed. The membrane performance was also evaluated using a laboratory pervaporation setup. Various process parameters, such as feed water concentration, downstream pressure, and temperature, were studied to interpret key indicators like total flux, partial fluxes, selectivity, and separation index. The temperature-dependent activation energy of the PVA, 1 %, and 2 % MWCNT membranes was estimated. At a feed concentration of 13 wt% water, the membrane doped with 2 wt% multi-walled carbon nanotubes (MWCNTs) exhibited a permeation flux of 0.226 kg/m2·h, a selectivity of 326.36, and an activation energy of 12.33 kJ/mol. Long-term stability of over 100 h confirmed the membrane's durability. Comparative analysis with commercial membranes revealed the superior efficiency and industrial potential of the MWCNT-doped membranes. Consequently, this study highlights the application of mixed matrix membranes through pervaporation to purify organic solvents from industrial streams, utilising eco-friendly and cost-efficient methodologies. © 2025 Elsevier B.V.