Chelate membrane from poly(vinyl alcohol)/poly( N ‐salicylidene allyl amine) blend. III. Effect of Mn(II) and Co(II) on oxygen/nitrogen separation

Facilitated transport of oxygen through Co(II) and Mn(II) chelate membranes from poly(vinyl alcohol)/poly( N ‐salicylidene allyl amine) was investigated. As the membranes became chelated, oxygen diffusivity decreased and the solubility toward oxygen was enhanced. The oxygen permeability of the base poly(vinyl alcohol)/poly( N ‐salicylidene allyl amine) membrane was 2.6 × 10 −3 cm 3 (STP)cm/cm 2 cm Hg sec (barrer), and the selectivity toward oxygen was 2.2. As Co(II) was introduced into this membrane, oxygen permeability and oxygen selectivity increased to 2.82 × 10 −2 barrer and 8.5, respectively. The permeability and selectivity of Mn(II) chelate membrane were 3.28 × 10 −2 and 5, respectively. A major reason for the increased selectivity was the enhanced solubility of oxygen in chelate membrane upon chelation. The transport behavior of chelate membranes followed a dual‐mode transport, and the parameters were estimated and compared between Co(II) and Mn(II) membranes. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 483–490, 1997