Sorption and permeation of acetic acid–water mixtures by pervaporation using copolymer membrane

Abstract

Poly (acrylonitrile‐co‐methyl acrylate) copolymer designated as PANMA was used for making pervaporation membrane. This membrane was used for separation of acetic acid–water mixtures over the concentration range of 80–99.5 wt% acetic acid in water. Interaction parameters based on Flory–Huggins lattice model and engaged species induced clustering (ENSIC) model was used to explain swelling of the membranes. Coupling in sorption was explained in terms of activity coefficient of water and acid in feed and membrane using Flory–Huggins model and also by interpolating ENSIC parameters. Flow coupling in pervaporation was also determined from phenomenological deviation coefficients. Intrinsic membrane properties like partial permeability and membrane selectivity of the solvents were also determined. Diffusion coefficient and plasticization coefficient of the solvents were obtained using a modified solution–diffusion model. The copolymer membrane showed high flux and water selectivity for highly concentrated acid. Thus, at 30°C temperature 1–20 wt% water in feed was concentrated to 82–84 wt% water in permeate and for 0.95 wt% water in feed, the membrane showed thickness normalized flux and water selectivity of 1.71 kg m−2 h−1 mμ and 409, respectively. OLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers

Tunable physicochemical properties of PVA nanocomposite membranes for enhanced pervaporation performance

“…The real factor behind pervaporation separation is the partial pressure difference on either side of the membrane. But in most of the literature selectivity is found to be the ratio of permeate and feed compositions which lack the real membrane properties . To overcome these limitations, Baker et al introduced a new factor called intrinsic selectivity that gives an obvious idea about the membrane performance.…”