Olefin Recovery by *BEA‐Type Zeolite Membrane: Affinity‐Based Separation with Olefin−Ag(+) Interaction

Ag(+) was introduced into *BEA‐type zeolite membrane by an ion‐exchange method to enhance olefin selectivity. Ag−*BEA membrane exhibited superior olefin separation performance for both ethylene/ethane and propylene/propane mixtures. Particularly, the separation factor for ethylene at 373 K reached 57 with the ethylene permeance of 1.6×10(−7) mol m(−2) s(−1) Pa(−1). Adsorption properties of olefin and paraffin were evaluated to discuss contribution of Ag(+) to separation performance enhancement. A strong interaction between olefin and Ag(+) in the membrane caused preferential adsorption of olefin against paraffin, leading to selective permeation of olefin. Ag−*BEA membrane also exhibited high olefin selectivities from olefin/N(2) mixtures. The affinity‐based separation through Ag−*BEA membrane showed a high potential for olefin recovery and purification from various gas mixtures.