Effective and efficient transport mechanism of CO$_2$ in subnano-porous crystalline membrane of syndiotactic polystyrene

Yoshinori Tamai

doi:10.1016/j.memsci.2021.120202

paper

Effective and efficient transport mechanism of CO $_{2}$ in subnano-porous crystalline membrane of syndiotactic polystyrene

arXiv:2201.04986 · doi:10.1016/j.memsci.2021.120202

Abstract

The gas permeation behavior in the single crystal of syndiotactic polystyrene (s-PS) S-I form was investigated in detail, in comparison to that in the s-PS $ε$ form. The S-I form exhibits high CO $_{2}$ /N $_{2}$ and CO $_{2}$ /CH $_{4}$ separation factors while preserving its high CO $_{2}$ permeability; a trade-off between selectivity and permeability was broken through.The mechanism of the effective and efficient transport of CO $_{2}$ in the S-I form was examined in relation to the cavity structure in the crystal. Because the CO $_{2}$ molecule is only fitted to the cavities in the S-I form, the solubility of CO $_{2}$ becomes high. In addition, tri-atomic molecules can more effectively diffuse in the S-I form compared with di-atomic molecules, as proved by the "long-gas" model. A novel design criterion for the CO $_{2}$ separation membranes is proposed based on the aspect of momentum transfer from polymer matrix to the penetrant.

Accepted version

Effective and efficient transport mechanism of CO2​ in subnano-porous crystalline membrane of syndiotactic polystyrene

Abstract

Effective and efficient transport mechanism of CO $_{2}$ in subnano-porous crystalline membrane of syndiotactic polystyrene