Process and device for the separation of an unsaturated hydrocarbon from a fluid mixture with other hydrocarbons

A process for the separation of at least one specific unsaturated hydrocarbon from a fluid mixture with other hydrocarbons which comprises:

• a first stage comprising (i) passing the fluid mixture containing said unsaturated hydrocarbon at superatmospheric pressure to one side of a first semiselective gas separation membrane with a non-porous active layer which is permeable to unsaturated hydrocarbons, and (ii) passing a stream comprising a liquid complexing agent on the other side of said first semiselective gas separation membrane, whereby the unsaturated hydrocarbon migrates through said first semiselective gas separation membrane with said non-porous active layer to the liquid, wherein said at least one specific unsaturated hydrocarbon is bound through complexation in the interface of the membrane and said liquid complexing agent;
• and
• a second stage which comprises (i) separating and removing the unsaturated hydrocarbon from the complexing agent, wherein in the second stage said unsaturated hydrocarbon is dissociated from the complexing agent by increasing the temperature, and (ii) the complexing agent is recycled.