Membrane Gas Separation

)
n-C
4
n-C
5
Figure 7.8 Permeability of (a) n - C 
4
and (b) n - C 
5
in Tefl on AF 2400 - based mixed matrices 
at 25 ° C, versus penetrant partial pressure. (c) Permeability ratio at infi nite dilution

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Vapor Sorption and Diffusion in Mixed Matrices Based on Tefl on® AF 2400 
141
method has proved to be useful also for the determination of the diffusion coeffi cient and 
for an estimation of the permeability in the composite materials. The evaluation of the 
contributions of the permeability can hence be used to determine the ideal selective 
behaviour of the composite membrane. 
We believe that the procedure can be properly applied also for the case of MMM 
obtained by loading glassy matrices with other nano - fi llers and can be a useful tool to 
develop better mixed matrix membranes.
Acknowledgements 
The fi nancial support of EU Strep NMP3 - CT - 2005 - 013644 (MultiMatDesign) is grate-
fully acknowledged. This work could not be possible without the experimental support 
of Lelio Basile. We also are grateful to Dr Tim Merkel of MTR for providing some of 
the samples characterized and for his precious advice.
References 
(1) T. - S. Chung , L. Y. Jiang , Y. Li , S. Kulprathipanja , Mixed matrix membranes (MMMs) com-
prising organic polymers with dispersed inorganic fi llers for gas separation 
,
Progress in 
Polymer Science , 32 , 483 ( 2007 ).
(2) T. C. Merkel , B. D. Freeman , R. J. Spontak , Z. He , I. Pinnau , P. Meakin , Ultrapermeable, 
reverse - selective nanocomposite membranes . Science , 296 , 519 – 522 ( 2002 ).
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