Olefin transport through membranes

Goering RM, Bowman CN, Koval CA, and Noble RD. Mechanisms of olefin transport through facilitated transport membranes. Polym Mater Sci Eng 1997 77 260-261. 

The selectivity of this type of membrane materials is based on a reversible specific interaction of the pi-electrons of olefins with certain metal ions, such as ionic silver, dissolved in the polymer matrix, which results in facilitated olefin transport of the ion-olefin coupling through the membrane. 

C.A. Koval and T. Spontarelli, Condensed phase facilitated transport of olefins through an ion exchange membrane, J. Am. Chem. Soc., 1988, 110, 293-295. 

Since the transport of a small molecule through a fixed carrier membrane depends largely on the kinetics, reversibility and affinity of the small molecule to the metal complex carrier, the transport properties of a small molecule are a good index for the activity of a metal complex in a macromolecule. Therefore, the following sections give a brief review of facilitated olefin and oxygen transport. 

In the above examples, both the feed and the permeate phases were gaseous and aqueous liquid membranes were used. Cahn and Li (1976) have demonstrated facilitated transport separation of the olefin 1-hexene from n-heptane through an aqueous membrane containing cuprous ammonium acetate the permeate phase was made up of n-octane. Kuo and Gregor (1983) have illustrated facilitated transport of acetic acid from an aqueous solution through an organic membrane of decaUn containing trioctylphosphine oxide (TOPO (0113(012)7)31 )), which complexed with acetic acid. 

Facilitated transport membranes have been studied for a long time. The earliest report was on the facilitated transport of oxygen through the hemoglobin solutions (Scholander, 1960). Since then, new membranes and new applications have emerged in many areas. Today, the potential applications of facilitated transport membranes include metal recovery, acid gas removal, bioseparations, olefin/paraffin separation, and O2/N2 separation. 

---