Graphene oxide reinforced facilitated transport membrane with poly(ionic liquid) and ionic liquid carriers for CO2/N2 separation

• Published in: Journal of membrane science 2021-11, Vol.638, p.119652, Article 119652
• Main Authors: Lee, Yun-Yang, Gurkan, Burcu
• Format: Article
• Language: English
• Subjects: CO2 capture; Cyanopyrrolide; Direct air capture; Poly(dialyldimethylamonium); Reactive separation
• ISSN: 0376-7388; 1873-3123
• DOI: 10.1016/j.memsci.2021.119652

CO2 capture technologies are essential to achieve the global goal of carbon neutral and carbon negative. Membrane separations are energy-efficient compared to the adsorption/absorption processes with sorbents/solvents. However, little attention has been given to CO2 separation from air (direct air capture: DAC) or cabin air by membranes. In this study, a thin film composite type of facilitated transport membrane (FTM) with a functionalized ionic liquid (IL) carrier is developed. The selective layer is an IL-rich gel nanoconfined within the graphene oxide nanosheet framework. High performance of CO2 carrier-facilitated transport at conditions relevant to DAC (3090 GPU and CO2/N2 selectivity of 1180) and cabin air (620 GPU and CO2/N2 selectivity of 250) was demonstrated at 295 K and 40% RH (1 GPU = 3.348 × 10-10 mol m-2 s-1 Pa−1). The coupled permeation and selectivity represent the best performing FTM known under DAC conditions and promise potential for CO2 separation from air. [Display omitted] •A composite membrane with ionic liquid carrier is developed for CO2/N2 separation.•CO2 permeance of 3090 GPU is achieved at 295 K, 40% RH with 410 ppm of CO2 feed.•A record breaking CO2/N2 selectivity of 1180 is demonstrated.•The inclusion of graphene oxide and poly(ionic liquid) enhanced membrane stability.•Membrane operates consistently over a 2-week long continuous separation.