Piperazine and its derivatives were incorporated into a thin film of poly(vinyl alcohol), and the CO2 separation performance of the resulting amin-containing membranes was investigated. The gas transport properties were dependent on the chemical structure of the amines. In particular, 3-(1-piperazinyl)-1,2-propanediol (PzPD)-containing polymeric membranes gave excellent CO2 separation properties over H2 and CH4 under humidity. CO2 interacted with the secondary amino group on the Pz ring to form a carbamate, which was readily hydrolyzed to produce bicarbonate ions. CO2 migrates through the membrane in the form of bicarbonate ions.
- Ikuo Taniguchi
- Kae Kinugasa
- Kanato Mitsuhara