title: Solvent resistant chitosan/poly(ether-block-amide) composite membranes for pervaporation of n-methyl-2-pyrrolidone/water mixtures.
abstract: A novel composite barrier comprising of hydrophilic and solvent resistant chitosan (CS) membrane on porous solvent resistant poly(ether-block-amide) (PEBA-2533) substrate was synthesized for pervaporation (PV) based dehydration of the polar aprotic n-methyl-2-pyrolidone (NMP) green solvent. The composite barrier was crosslinked with tetraethyl orthosilicate (TEOS) to control swelling and enhance selectivity. Operating parameters such as feed water concentration, permeate pressure and membrane thickness were varied to assess membrane flux and selectivity. A two-dimensional finite element method (FEM) model was developed to predict the concentration profile within the membrane through computational fluid dynamics (CFD). On the basis of complete mixing experiments, a numerical simulation was performed to predict membrane area requirement and exit streams' compositions for commercial pervaporation units operated in plug flow mode. Both unmodified chitosan and tetraethyl orthosilicate crosslinked composite membranes successfully separated feed mixture containing 4.6 wt% water by exhibiting water fluxes of 0.024 and 0.019 kg/m(2)h, whereas the corresponding selectivities were found to be as high as 182 and 225, respectively.
authors.affiliation: Membrane Separations Group, Chemical Engineering Division, Indian Institute of Chemical Technology, Hyderabad 500007, India.
authors.forename: N Shiva
authors.initials: NS
authors.lastname: Prasad
authors.affiliation: Membrane Separations Group, Chemical Engineering Division, Indian Institute of Chemical Technology, Hyderabad 500007, India.
authors.forename: Siddhartha
authors.initials: S
authors.lastname: Moulik
authors.affiliation: Membrane Separations Group, Chemical Engineering Division, Indian Institute of Chemical Technology, Hyderabad 500007, India.
authors.forename: Subha
authors.initials: S
authors.lastname: Bohra
authors.affiliation: Process Simulation and Control Group, Chemical Engineering Division, Indian Institute of Chemical Technology, Hyderabad 500007, India.
authors.forename: K Yamuna
authors.initials: KY
authors.lastname: Rani
authors.affiliation: Membrane Separations Group, Chemical Engineering Division, Indian Institute of Chemical Technology, Hyderabad 500007, India. Electronic address: sridhar11in@yahoo.com.
authors.forename: S
authors.initials: S
authors.lastname: Sridhar
mesh_terms: D048271:Chitosan / Q000031:analogs & derivatives* / Q000737:chemistry; D004058:Diffusion; D057446:Hydrodynamics; D008567:Membranes, Artificial; D010539:Permeability; D011108:Polymers / Q000737:chemistry*; D011312:Pressure; D011760:Pyrrolidinones / Q000737:chemistry*; D013718:Tensile Strength; D014835:Volatilization; D014867:Water / Q000737:chemistry*
chemical_list: D008567:Membranes, Artificial; D011108:Polymers; D011760:Pyrrolidinones; C000610469:chitosan poly(ether-block-amide); D014867:Water; D048271:Chitosan; C038678:N-methylpyrrolidone
keywords: CFD; Chitosan/poly(ether-block-amide) composite membrane; Pervaporation; Plug flow model; n-Methyl-2-pyrolidone/water mixtures