Three displacement chromatography processes were experimentally studied for gas mixtures. Process A is standard displacement chromatography applied to gases. Process B involves the column being initially saturated with the most weakly adsorbed species in the feed instead of using a carrier gas. Process C uses the most strongly adsorbed component in the feed as the desorbent. Processes B and C are novel. The gas system studied consists of a 50%/50% methane/ethane feed mixture in Processes A and B and a 50%/30%/20% methane/ethane/propane feed mixture in Process C. Propane is used as the desorbent in all three processes. Hydrogen or helium is used as the presaturant in Process A. The adsorbent used was zeolite 5A. Processes A, B, and C were all found to produce bands of pure components when the appropriate feed time was used. The amount of ethane input into the column was crucial to obtain good separations. A local equilibrium theory was developed and predictions from the theory were compared with experimental results.