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Abstract A field trial with 1.4 m2 spiral-wound (SW) membrane modules fabricated from an amine-containing facilitated transport membrane was conducted with actual flue gas at the National Carbon Capture Center in Wilsonville, AL, U.S.A. Prior to the field test, the membrane modules were systematically evaluated with simulated flue gas to identify the optimal operating conditions, including feed flow rate, feed pressure and operating temperature. With the actual flue gas, the membrane modules showed ca. 1450 GPU CO 2 permeance and 185 CO 2 /N 2 selectivity at 67 °C with feed and permeate pressures of 4 and 0.3 atm, respectively. A 500-h stability was demonstrated in spite of the interference of system upsets and flue gas outages. During the field trial, carbon capture rates of better than 40% were achieved by a single SW module with coal-derived flue gas. Except for a few flue gas upsets, the CO 2 purities in the captured stream were 94.5% or better on dry basis. The data obtained from this project validates the membrane material and provide basis for the design and fabrication of full-scale SW module with a membrane area larger than 50 m2. It should be noted that no significant amounts of Cr, As and Se were deposited onto the membrane during this 500-h test. Highlights • 1.4 m2 spiral-wound modules of a facilitated transport membrane were fabricated. • A field trail was conducted with actual flue gas containing SO x , NO x and O 2. • Performance depended strongly on feed flow rate, pressure and temperature. • 500-h stable performance was demonstrated despite several flue gas outages. • > 40% CO 2 recovery and > 94.5% CO 2 purity were achieved by a single module. [ABSTRACT FROM AUTHOR]

Abstract The facilitated transport of CO 2 through an amine-containing polymeric membrane on a nanoporous PES substrate was studied at large feed-to-permeate pressure differentials that are relevant to post-combustion carbon capture. With the selective layer reinforced mechanically by incorporation of carbon nanotubes, the carrier saturation of amino groups by excessive CO 2 was observed at high feed or permeate vacuum pressure. Nearly complete carrier saturation was observed at 7 atm feed pressure or a permeate vacuum near ambient pressure. At relatively low vacuum pressures, the vacuum degree and operating temperature affected the CO 2 transport simultaneously. A vacuum pressure significantly lower than the water saturation pressure at certain temperature resulted in the dehydration of the selective layer, thereby a reduced CO 2 permeance. This dehydration was mitigated at a moderate vacuum pressure. At the moderate vacuum pressure, the nanoporous PES substrate controlled the water permeation, leading to a sufficiently hydrated selective layer with high CO 2 permeance and CO 2 /N 2 selectivity. Overall, the membrane performed well with 0.3–0.6 atm vacuum pressures at 67 °C and a feed pressure of 4 atm, achieving the best membrane performance with a CO 2 permeance of 1451 GPU and a CO 2 /N 2 selectivity of 165. Highlights • Facilitated transport membrane was characterized with large pressure differentials. • Carrier saturation occurred at a high feed or vacuum pressure. • Vacuum pressure affected the hydration of the amine-containing selective layer. • Higher temperature enhanced membrane performance due to faster reaction kinetics. • 1451 GPU CO 2 permeance and 165 CO 2 /N 2 selectivity were obtained at 67 °C. [ABSTRACT FROM AUTHOR]

Abstract Fabrication of amine-containing membranes for removal of H 2 S and CO 2 from reformate gas for hydrogen purification for fuel cells was scaled up by using a continuous roll-to-roll membrane fabrication machine. The membrane contained aminoisobutyric acid-potassium salt as the mobile carrier and polyvinylamine as the fixed-site carrier for facilitated transport of acid gases in crosslinked polyvinylalcohol as the membrane matrix. Three key variables controlling the membrane selective layer thickness, i.e., the coating solution, substrate web coating speed, and coating knife gap setting, were identified and studied. Membranes in 14 in. in width and > 150 feet in length were fabricated with a uniform selective layer thickness of around 15 µm. The scale-up membranes demonstrated similar performances as the lab-scale membranes with a CO 2 permeance of more than 200 GPU, CO 2 /H 2 selectivity of greater than 200, and H 2 S/H 2 selectivity of higher than 600. The scale-up membranes were used for the fabrication of prototype spiral-wound membrane modules for a field test with autothermal reformate gas as the feed gas. The modeling and optimization of the hydrogen purification process were performed to identify the optimum test conditions for the spiral-wound membrane modules. The modeling results showed that the membrane removed H 2 S to less than 10 ppm and CO 2 to < 1% in the hydrogen product with more than 99% of H 2 recovery for the case of using a wet sweep gas with 40% moisture. The field test results showed that the H 2 S and CO 2 concentrations were about 4–10 ppm and < 3%, respectively, in the hydrogen product on a wet basis and that the agreement between the modeling results and the test results was reasonably good. Highlights • Fabrication of amine-containing CO 2 -selective membrane for H 2 S removal was scaled up. • Scale-up membranes were tested with both simulated and actual reformate gases as the feed gases. • Modeling and process optimization were performed to identify the optimum module test conditions. • Good membrane performance was obtained in agreement with the modeling results. • Field test results have shown the potential for H 2 S removal in fuel cell application. [ABSTRACT FROM AUTHOR]

Facilitated transport membranes for CO 2 capture from flue gas were scaled up and subsequently fabricated into spiral-wound modules. In order to increase the membrane area in each module conveniently, a multi-leaf rolling procedure utilizing a carrier layer was used, and the fabrication steps were documented in detail. The prototype module comprised up to 7 membrane leaves (each membrane leaf had dimensions of 14″ by 36″) and had a total membrane area of up to 2.94 m2. By controlling the spacer thicknesses, the packing density in each of the modules was enhanced, while the pressure drops on both feed and permeate sides were maintained below 1.5 psi/m. The fabricated membrane modules showed consistent transport results as the corresponding scale-up membranes. For instance, a CO 2 permeance of 1450 GPU and a CO 2 /N 2 selectivity of 185 were achieved with a simulated flue gas at 67 °C. Furthermore, the pressure drop and concentration polarization phenomenon were quantitatively correlated to the feed flow rate. The developed correlations were used to predict the separation performance of a full-size (8″ × 40″) module. • Fabrication procedure of multi-leaf spiral-wound module is detailed. • Suitable spacers were identified to achieve optimal module performance. • Modules each with 2.94 m2 area were attained through facile scale-up procedure. • Commercial-size module of 70.4 m2 is predicted based on rolling materials. • Pressure drop and concentration polarization were included in module modeling. [ABSTRACT FROM AUTHOR]