Permylene uses a natural source polymer facilitated transport membrane designed for industrial conditions. Steady and stable olefin transport is achieved in continuous, non-stop operation via circulation of an aqueous silver nitrate solution over a spiral wound membrane containing a hydrogel coating. The silver ions in the silver nitrate solution within the hydrogel structure form a reversible complex with the double bonds of the olefin molecules. Any molecules not possessing a double bond are rejected, resulting in excellent selectivity. The process is primarily driven by the olefin partial pressure differential across the Permylene membrane resulting in commercially attractive permeation rates.