title: Preparation, characterization and gas permeation investigation of resorcinol-formaldehyde polymer or carbon xerogels/tubular ceramic composites.
abstract: New very stable composites prepared by deposition of resorcinol-formaldehyde polymer (RF-) or carbon (C-) xerogels into walls of commercial porous tubular ceramics (TiO2-ZrO2 and alphaAl2O3-gammaAl203) were obtained by a sol-gel process followed by a drying and a pyrolytic (only for C-xerogel/ceramic composites) step. They were characterized by nitrogen adsorption-desorption, SEM and XRD, and tested for gas (H2, CH4, CO2 and CO) separation applications. Additional morpho-structural information about the open-interconnected ultramicropore structure of composites was found by gas permeation investigation. Interesting results for H2 permeance was obtained especially for RF-polymer/ceramic composites respecting Knudsen diffusion mechanism of gas permeance: H2 > CH4 > CO > CO2. The coexistence of Knudsen and surface diffusion mechanisms were confirmed.
authors.affiliation: "Babes-Bolyai" University, Faculty of Chemistry and Chemical Engineering, Arany Janos st., 11, Cluj-Napoca, RO-400028, Romania. ccosmin@chem.ubbcluj.ro
authors.forename: Liviu Cosmin
authors.initials: LC
authors.lastname: Cotet
authors.forename: Kelly
authors.initials: K
authors.lastname: Briceño
authors.forename: Carmen Ioana
authors.initials: CI
authors.lastname: Fort
authors.forename: Virginia
authors.initials: V
authors.lastname: Danciu
authors.forename: Ricard
authors.initials: R
authors.lastname: Garcia-Valls
authors.forename: Daniel
authors.initials: D
authors.lastname: Montané