Membrane Absorption of Ethylene from a Mixture with Ethane Using MDK-3 Composite Membranes

Separation of olefin/paraffin mixtures is an important problem. The use of a gas—liquid membrane contactor is an attractive alternative to traditional power-consuming cryogenic distillation methods. The paper deals with the separation of ethylene from its mixture with ethane (component ratio 19/81 vol %, respectively) using an aqueous silver nitrate solution as a selective ethylene absorbent in a flat-sheet lab-scale membrane module equipped with an MDK-3 commercial composite membrane with the selective layer based on silicone rubber. The effect of the absorbent and gas mixture feed linear velocities on the residual ethylene content of the mixture is considered. The thin selective layer of the membrane is shown to preserve high performance during long-term experimental run ensuring high mass-exchange characteristics and preventing the absorbent penetration into the porous structure of the membrane support.