title: Interfacial Design of Ternary Mixed Matrix Membranes Containing Pebax 1657/Silver-Nanopowder/[BMIM][BF4] for Improved CO2Separation Performance.
abstract: In this research, Pebax1657 as an organic phase and silver nanoparticles as an inorganic phase were used for preparation of binary mixed matrix membranes (MMMs). Silver nanoparticles as a filler could enter the polymer chains and enhance the gas permeability by increasing the fractional free volume of membranes. Afterward, ternary MMMs were fabricated by addition of 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF4]) ionic liquid, in order to have better polymer/filler adhesion and eliminate interfacial defects and nonselective voids. In addition, positively polarized silver nanoparticles in the presence of the IL could interact with PEO segment of the polymer and increase the CO2affinity of membranes, which results in increasing the CO2/light gases permselectivity of MMMs. Gas permeation properties of MMMs were studied at a temperature of 35 °C and operating pressures from 2 to 10 bar. Moreover, fabricated membranes were characterized by fourier transform infrared-attenuated total reflectance (FTIR-ATR), scanning electron microscopy (SEM), X-ray diffraction (XRD), and differential scanning calorimeter (DSC). The analysis revealed that there is a proper adhesion between positively charged surface of nanoparticles and the polymer, and both filler and IL decrease the crystallinity of the membranes, which could enhance the polar gas transport properties. Gas permeation results showed significant enhancement in CO2permeability (325 Barrer) for binary membrane (Pebax 1657/1%Ag) at 35 °C and 10 bar. Moreover, ternary MMM (Pebax 1657/0.5%Ag/50%IL) encountered significant increase in both permeability and selectivity in comparison with neat membrane. Indeed, the CO2permeability increased from 110 Barrer to 180 (about 64%). Moreover, the related CO2/CH4and CO2/N2selectivities were increased from 20.8 to 61.0 (more than 193%) and from 78.6 to 187.5 (about 139%), respectively.
authors.affiliation: Faculty of Chemical Engineering, Tarbiat Modares University , P.O. Box 14115-143, Tehran, Iran.
authors.forename: Ehsan
authors.initials: E
authors.lastname: Ghasemi Estahbanati
authors.affiliation: Faculty of Chemical Engineering, Tarbiat Modares University , P.O. Box 14115-143, Tehran, Iran.
authors.forename: Mohammadreza
authors.identifier: http://orcid.org/0000-0001-5307-8010
authors.initials: M
authors.lastname: Omidkhah
authors.affiliation: Department of Chemical Engineering, Faculty of Engineering, Arak University , Arak 38156-8-8349, Iran.
authors.forename: Abtin
authors.initials: A
authors.lastname: Ebadi Amooghin
keywords: ([BMIM][BF4]) ionic Liquid; Ag nanoparticles; CO2 permselectivity; Pebax 1657 copolymer; binary and ternary MMMs; gas separation