Olefin separation processes may comprise: introducing a first aqueous salt stream and a mixed feed stream comprising at least one olefin to a salt ion membrane; obtaining an olefin-rich permeate stream and an olefin-lean retentate stream from the salt ion membrane, at least the olefin-lean retentate stream comprising a salt ion membrane aqueous salt phase; introducing the olefin-lean retentate stream to a separation device to obtain a first portion comprising a hydrocarbon stream and a second portion comprising the salt ion membrane aqueous salt phase; introducing to an absorption device the hydrocarbon stream and a second aqueous salt stream under conditions effective to promote olefin extraction, in which the salt ion membrane aqueous salt phase is provided as a portion of the second aqueous salt stream; and obtaining an olefin-rich aqueous salt stream from the absorption device that is provided as at least a portion of the first aqueous salt stream.