High-performance carbon molecular sieve membranes for ethylene/ethane separation derived from an intrinsically microporous polyimide

Handle URI:
http://hdl.handle.net/10754/582485
Title:
High-performance carbon molecular sieve membranes for ethylene/ethane separation derived from an intrinsically microporous polyimide
Authors:
Salinas, Octavio ( 0000-0003-0653-660X ) ; Ma, Xiaohua; Litwiller, Eric ( 0000-0001-5366-0967 ) ; Pinnau, Ingo ( 0000-0003-3040-9088 )
Abstract:
An intrinsically microporous polymer with hydroxyl functionalities, PIM-6FDA-OH, was used as a precursor for various types of carbon molecular sieve (CMS) membranes for ethylene/ethane separation. The pristine polyimide films were heated under controlled N2 atmosphere at different stages from 500 to 800 °C. All CMS samples carbonized above 600 °C surpassed the polymeric ethylene/ethane upper bound. Pure-gas selectivity reached 17.5 for the CMS carbonized at 800 °C with an ethylene permeability of about 10 Barrer at 2 bar and 35 °C, becoming the most selective CMS for ethylene/ethane separation reported to date. As expected, gravimetric sorption experiments showed that all CMS membranes had ethylene/ethane solubility selectivities close to one. The permselectivity increased with increasing pyrolysis temperature due to densification of the micropores in the CMS membranes, leading to enhanced diffusivity selectivity. Mixed-gas tests with a binary 50:50 v/v ethylene/ethane feed showed a decrease in selectivity from 14 to 8.3 as the total feed pressure was increased from 4 to 20 bar. The selectivity drop under mixed-gas conditions was attributed to non-ideal effects: (i) Competitive sorption that reduced the permeability of ethylene and (ii) dilation of the CMS that resulted in an increase in the ethane permeability.
KAUST Department:
Advanced Membranes and Porous Materials Research Center; Physical Sciences and Engineering (PSE) Division
Citation:
High-performance carbon molecular sieve membranes for ethylene/ethane separation derived from an intrinsically microporous polyimide 2015 Journal of Membrane Science
Publisher:
Elsevier BV
Journal:
Journal of Membrane Science
Issue Date:
18-Nov-2015
DOI:
10.1016/j.memsci.2015.11.013
Type:
Article
ISSN:
03767388
Additional Links:
http://linkinghub.elsevier.com/retrieve/pii/S037673881530315X
Appears in Collections:
Articles; Advanced Membranes and Porous Materials Research Center; Physical Sciences and Engineering (PSE) Division

Full metadata record

DC FieldValue Language
dc.contributor.authorSalinas, Octavioen
dc.contributor.authorMa, Xiaohuaen
dc.contributor.authorLitwiller, Ericen
dc.contributor.authorPinnau, Ingoen
dc.date.accessioned2015-11-22T12:04:00Zen
dc.date.available2015-11-22T12:04:00Zen
dc.date.issued2015-11-18en
dc.identifier.citationHigh-performance carbon molecular sieve membranes for ethylene/ethane separation derived from an intrinsically microporous polyimide 2015 Journal of Membrane Scienceen
dc.identifier.issn03767388en
dc.identifier.doi10.1016/j.memsci.2015.11.013en
dc.identifier.urihttp://hdl.handle.net/10754/582485en
dc.description.abstractAn intrinsically microporous polymer with hydroxyl functionalities, PIM-6FDA-OH, was used as a precursor for various types of carbon molecular sieve (CMS) membranes for ethylene/ethane separation. The pristine polyimide films were heated under controlled N2 atmosphere at different stages from 500 to 800 °C. All CMS samples carbonized above 600 °C surpassed the polymeric ethylene/ethane upper bound. Pure-gas selectivity reached 17.5 for the CMS carbonized at 800 °C with an ethylene permeability of about 10 Barrer at 2 bar and 35 °C, becoming the most selective CMS for ethylene/ethane separation reported to date. As expected, gravimetric sorption experiments showed that all CMS membranes had ethylene/ethane solubility selectivities close to one. The permselectivity increased with increasing pyrolysis temperature due to densification of the micropores in the CMS membranes, leading to enhanced diffusivity selectivity. Mixed-gas tests with a binary 50:50 v/v ethylene/ethane feed showed a decrease in selectivity from 14 to 8.3 as the total feed pressure was increased from 4 to 20 bar. The selectivity drop under mixed-gas conditions was attributed to non-ideal effects: (i) Competitive sorption that reduced the permeability of ethylene and (ii) dilation of the CMS that resulted in an increase in the ethane permeability.en
dc.language.isoenen
dc.publisherElsevier BVen
dc.relation.urlhttp://linkinghub.elsevier.com/retrieve/pii/S037673881530315Xen
dc.rightsNOTICE: this is the author’s version of a work that was accepted for publication in Journal of Membrane Science. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Journal of Membrane Science, 18 November 2015. DOI: 10.1016/j.memsci.2015.11.013en
dc.subjectEthylene/ethane separationen
dc.subjectCarbon molecular sieveen
dc.subjectPolyimide of intrinsic microporosityen
dc.subjectMixed-gas permeationen
dc.titleHigh-performance carbon molecular sieve membranes for ethylene/ethane separation derived from an intrinsically microporous polyimideen
dc.typeArticleen
dc.contributor.departmentAdvanced Membranes and Porous Materials Research Centeren
dc.contributor.departmentPhysical Sciences and Engineering (PSE) Divisionen
dc.identifier.journalJournal of Membrane Scienceen
dc.eprint.versionPost-printen
dc.contributor.affiliationKing Abdullah University of Science and Technology (KAUST)en
kaust.authorSalinas, Octavioen
kaust.authorMa, Xiaohuaen
kaust.authorLitwiller, Ericen
kaust.authorPinnau, Ingoen
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