title: Enhanced pervaporation performance of multi-layer PDMS/PVDF composite membrane for ethanol recovery from aqueous solution.
abstract: Multi-layer PDMS/PVDF composite membrane with an alternative PDMS/PVDF/non-woven-fiber/PVDF/PDMS configuration was prepared in this paper. The porous PVDF substrate was obtained by casting PVDF solution on both sides of non-woven fiber with immersion precipitation phase inversion method. Polydimethylsiloxane (PDMS) was then cured by phenyltrimethoxylsilane (PTMOS) and coated onto the surface of porous PVDF substrate one layer by the other to obtain multi-layer PDMS/PVDF composite membrane. The multi-layer composite membrane was used for ethanol recovery from aqueous solution by pervaporation, and exhibited enhanced separation performance compared with one side PDMS/PVDF composite membranes, especially in the low ethanol concentration range. The maximum separation factor of multi-layer PDMS/PVDF composite membrane was obtained at 60 degrees C, and the total flux increased exponentially along with the increase of temperature. The composite membrane gave the best pervaporation performance with a separation factor of 15, permeation rate of 450 g/m(2)h with a 5 wt.% ethanol concentration at 60 degrees C.
authors.affiliation: Membrane Technology & Engineering Research Center, Department of Chemical Engineering, Tsinghua University, Beijing, People's Republic of China.
authors.forename: Xia
authors.initials: X
authors.lastname: Zhan
authors.forename: Jiding
authors.initials: J
authors.lastname: Li
authors.forename: Junqi
authors.initials: J
authors.lastname: Huang
authors.forename: Cuixian
authors.initials: C
authors.lastname: Chen
mesh_terms: D000327:Adsorption; D004129:Dimethylpolysiloxanes / Q000737:chemistry*; D000431:Ethanol / Q000737:chemistry / Q000302:isolation & purification*; D008567:Membranes, Artificial; D011145:Polyvinyls / Q000737:chemistry*; D016062:Porosity; D013696:Temperature; D005465:Fluorocarbon Polymers
chemical_list: D004129:Dimethylpolysiloxanes; D000431:Ethanol; D008567:Membranes, Artificial; D011145:Polyvinyls; C024865:polyvinylidene fluoride; D005465:Fluorocarbon Polymers; C013830:baysilon