A mixed matrix membrane for separating gas components from a mixture of
gas components is disclosed. The membrane comprises a continuous phase
polymer with inorganic porous particles, preferably molecular sieves,
interspersed in the polymer. The polymer has a CO.sub.2/CH.sub.4
selectivity of at least 20 and the porous particles have a mesoporosity
of at least 0.1 cc STP/g. The mixed matrix membrane exhibits an increase
in permeability of least 30% with any decrease in selectivity being no
more than 10% relative to a membrane made of the neat polymer. The porous
particles may include, but are not limited to, molecular sieves such as
CVX-7 and SSZ-13, and/or other molecular sieves having the required
mesoporosity. A method for making the mixed matrix membrane is also
described. Further, a method is disclosed for separating gas components
from a mixture of gas components using the mixed matrix membrane with
mesoporous particles.