Sorption thermodynamics and coupling effect for pervaporative dehydration of acetone through nanoclay and iron nanoparticle-filled copolymer membranes

摘要

Sodium montmorillonite (NaMMT) nanoclay particles were incorporated in-situ in the copolymer matrix of Poly (acrylonitrile-co-ethyl acrylate) during its synthesis from different molar% of acrylonitrile (AN) and ethyl acrylate (EA) monomers by emulsion polymerization. Similar polymerization was also carried out in the presence of iron salts to generate iron nanoparticles (FeNP) in situ in the membrane matrix. The membranes were characterized by FTIR, NMR, molecular weight (M-v), XRD, DTA-TGA, SEM, TEM, EDAX, contact angles for hydrophilicity and mechanical properties. The sorption and permeation of acetone-water binary mixtures through these membranes were analyzed in terms of solvent-solvent and solvent-membranes interaction and also by solvent coupling with Flory-Huggins, ENSIC and six-parameter solution diffusion model. The synthesis variables were optimized with the central composite design (CCD) of response surface methodology (RSM). The filled membranes showed high sorption and pervaporation selectivity for water for dehydration of acetone, while for similar filler loading FeNP-filled membranes showed higher flux and selectivity than NaMMT clay filled membrane. The membrane prepared with AN:EA molar ratio of 5:1 and filled with 2 wt% NaMMT clay showed a flux(kg/m(2)h)/selectivity of 0.903/125.2, which further increased to 0.937/140 for the same membrane filled with 5 wt% FeNP for 90 wt% feed acetone.