Reverse selectivity in poly dimethyl siloxane/Au nanocomposite membrane in Co2/Ch4 separation

A novel nanocomposite membrane, poly dimethyl siloxane (PDMS)/Au was prepared for CO2/CH4 separation. The effect of filler loading on permselectivity, diffusivity selectivity and solubility selectivity was reported for CO2/CH4 separation. The pure polymer shows permeation to gas molecules in the order of their kinetic diameter was close to unity. But for the Au/PDMS, there was a reverse selective phenomenon of CO2 at its percolation threshold. CO2 had a quadrupole moment, and was expected to be more soluble in polymer with polar group. However, the interaction of PDMS and Au NP could have reduced the polarity of hybrid membrane. This is an abstract of a paper presented at the 2006 AIChE Annual Meeting (San Francisco, CA 11/12-17/2006).