(293a) New Facilitated Transport Membrane and Process for CO2 Capture from Flue Gas
AIChE Annual Meeting
2023
2023 AIChE Annual Meeting
Catalysis and Reaction Engineering Division
In Honor of the 2021 R.H. Wilhelm Award Winner I (Invited Talks)
Wednesday, November 8, 2023 - 8:00am to 8:16am
Application of membrane for CO2 capture from flue gas has been limited by the trade-off between CO2 permeance and CO2/N2 selectivity for most polymeric membrane materials. To overcome this limitation, we have studied the facilitated transport membrane (FTM) possessing both high permeance and selectivity and designed a membrane process that can capitalize on high-selectivity offered by FTM. We have elucidated the carrier saturation phenomenon, characteristic of FTMs, using a new FTM containing the aminoacid salt of 2-(1-piperazinyl)ethylamine sarcosinate as mobile carrier and polyvinylamine as fixed-site carrier. The membrane was used to fabricate 1.4-m2 spiral-wound modules, which exhibited a CO2 permeance of 1450 GPU and a CO2/N2 selectivity of 185 at 67°C with actual coal-derived flue gas at the National Carbon Capture Center (NCCC) in Wilsonville, AL, USA. Furthermore, a significant increase in CO2 permeance has been achieved upon the bulk removal of CO2 for the range of CO2 partial pressures relevant to carbon capture from coal flue gas. For instance, the CO2 permeance increased from 1464 to 1918 GPU when the CO2 partial pressure reduced from 74.1 to 3.9 kPa at 67°C. Such a carrier saturation phenomenon has been modeled and incorporated into a novel 2-stage membrane process featuring partial retentate recycle. As the bulk CO2 removal reduces the CO2 partial pressure gradually in the membrane module, this feature mitigates the carrier saturation and results in an uprising CO2 permeance upon the CO2 removal. In addition, an integrated skid of the 2-stage membrane process was tested at the NCCC with an actual natural gas flue gas, demonstrating 90 â 99% CO2 capture degrees, all with â¥95% purity (on dry basis), during the parametric testing and at steady state for 500 h cumulatively with 91.0% CO2 capture and >95% CO2 purity.