In this research, the effects of Zeolite 4Å and ZSM-5 on the separation of C2H6 and C3H8 from CH4 through
polyurethane/zeolite mixed matrix membranes (MMM) are evaluated. Physical properties of synthesized
polyurethane and polyurethane/zeolite MMM were investigated by FTIR, XRD, TGA and SEM analyses.
Results indicate that phase separation of hard and soft segments in polyurethane would be increased
by adding butanediamine (BDA) chain extender in polymer due to the generation of more hydrogen
bonds between hard segment domains. The obtained SEM micrographs confirm that the Zeolite is distributed
in the polymer matrix homogenously. The results of gas permeation represent that permeability and
selectivity of Hydrocarbons are increased by increasing the urea groups in the polymer structure. Moreover,
the obtained results of gas permeation of polyurethane–zeolite (4Å) membranes indicate an
increase in the permeability of Methane, with the reduction in C2H6/CH4 and C3H8/CH4 selectivity by
increasing the Zeolite 4Å up to 10 wt%. In addition, the results of the gas permeation of polyurethane–
zeolite (ZSM-5) MMM indicate a significant increment in permeability and selectivity of all Hydrocarbons.
The permeability of Propane and its selectivity over Methane is increased from 64.8 Barrer and
2.6 into 117.2 Barrer and 3.64 in with 20 wt% filled PU–ZSM 5 MMM, respectively.