Zeinab Rajabi - Membrane Processes Research Laboratory (MPRL), Department of Petrochemical Engineering,Amirkabir University of Technology (Tehran Polytechnic), Mahshahr Campus, Mahshahr, Iran.
Faramarz Afshar Taromi - Department of Polymer Engineering & Color Technology, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran.
Ali Kargari - Membrane Processes Research Laboratory (MPRL), Department of Petrochemical Engineering,Amirkabir University of Technology (Tehran Polytechnic), Mahshahr Campus, Mahshahr, Iran.

A novel of nanocomposite membranes, consisting of MWCNTs embedded in Ethylene Propylene diene monomer (EPDM) was prepared. Crude MWCNTs were chemically treated using strong acids (H2SO4/HNO3) to produce the functional carboxyl groups (COOH) on their surfaces. The results from FTIR analysis confirmed that chemical modification on carbon nanotubes had taken place. The effects of adding different amounts of R-MWCNTs and C-MWCNTs on morphology and separation of CO2/N2 gases of nanocomposie membranes at different pressures were investigated. Due to better dispersion of functionalized MWCNTs and stronger interaction the carboxyl groups with of polar gases like CO2, the CO2/N2 gas selectivity for the C-MWCNT/EPDM membranes are higher than those of R-MWCNT/EPDM membrane. The maximun selectivity was achieved 24.41 at 2 bar pressure for 0.75 wt.% of C-MWCNT into EPDM matrix

nanocomposite membrane- functionalization- EPDM- MWCNT- gas separation