Fabrication and gas separation properties of polybenzimidazole (PBI)/nanoporous silicates hybrid membranes

Sunho Choi, Joaquin Coronas, Zhiping Lai, David Yust, Frank Onorato, Michael Tsapatsis*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

68 Scopus citations


Composites of polybenzimidazole (PBI) with proton-exchanged AMH-3 and swollen AMH-3 were prepared, characterized by electron microscopy and X-ray scattering and tested for hydrogen/carbon dioxide ideal selectivity. Proton-exchanged AMH-3 was prepared under mild conditions by the ion exchange of Sr and Na cations in the original AMH-3 using aqueous solution of dl-histidine. Swollen AMH-3 was prepared by sequential intercalation of dodecylamine following the ion exchange in the presence of dl-histidine. Both silicate materials were introduced into a continuous phase of PBI as a selective phase. Mixed matrix nanocomposite membranes, prepared under certain casting conditions, with only 3 wt% of swollen AMH-3 present substantial increase of hydrogen/carbon dioxide ideal selectivity at 35 °C, i.e., more than by a factor of 2 compared to pure PBI membranes (40 vs. 15). Similar ideal selectivity was observed using higher loadings (e.g., 14%) of proton-exchanged AMH-3 particles suggesting that transport of hydrogen is faster than carbon dioxide in AMH-3-derived silicates. However, the ideal selectivity of mixed matrix membranes approaches that of pure polymer as the operating temperature increases to 100 °C and 200 °C. The composite membranes with AMH-3-derived materials were compared with MCM-22/PBI membranes. Composite membranes incorporating MCM-22 plate-like crystals show no selectivity enhancements possibly due to the presence of larger pores in MCM-22.

Original languageEnglish (US)
Pages (from-to)145-152
Number of pages8
JournalJournal of Membrane Science
Issue number1-2
StatePublished - May 15 2008

Bibliographical note

Funding Information:
Funding for this work was provided mainly by NSF (CTS-0327811). Additional support was provided by DOE (DE-FG26-04NT42119) and Pall Corporation. Joaquin Coronas acknowledges support from the Spanish Ministry of Education (Programa de Estancias de Profesores de Universidad of the Dirección General de Universidades).


  • Gas separation
  • Layered silicate
  • Mixed matrix
  • Nanocomposite
  • Polymer

ASJC Scopus subject areas

  • Biochemistry
  • General Materials Science
  • Physical and Theoretical Chemistry
  • Filtration and Separation


Dive into the research topics of 'Fabrication and gas separation properties of polybenzimidazole (PBI)/nanoporous silicates hybrid membranes'. Together they form a unique fingerprint.

Cite this