Polyphosphazene gas separation membranes

Claim 1

A process for separating acid gases from non-acid gases comprising: contacting a gaseous feed mixture of acid gases and non-acid gases with a first surface of a separation membrane comprising polyphosphazenes having a preferential selectivity and permeability for the acid gases and represented by the formula: ##STR4## where n is between about 100 and about 70,000; where Y and Y' are the same or different and are comprised of oxygen, sulfur or nitrogen; R and R' are the same or different and are comprised of alkyl, aryl, substituted alkyl, or substituted aryl groups, each group having from 1 to about 25 carbon atoms; maintaining a second surface of the polyphosphazene membrane at a lower chemical potential for the acid gases than the chemical potential at the first surface; permeating the acid gases into and through the polyphosphazene membrane; and removing from the vicinity of the second surface a permeated product having a greater concentration of acid gases relative to non-acid gases than contained in the gaseous feed mixture.