Separation of gas mixtures using Co(II) carborane-based porous coordination polymers

Separations of CO(2)/CH(4), CO(2)/N(2), and O(2)/N(2) mixtures were studied in three porous coordination polymers made of the same carborane ligand and Co(II) nodes. High selectivities for CO(2) over CH(4) (similar to 47) and CO(2) over N(2) (similar to 95) were obtained, especially in the material with coordinated pyridine. Unusual selectivity for O(2) over N(2) (as high as 6.5) was demonstrated in the materials with open Co(II) sites.