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Mixed Gas Diffusion in the Polymer of Intrinsic Microporosity PIM-SBF-1. 21. (a). (b). SI Figure 4. Comparison of the increasing feed pressure as a function of time ...

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Supplementary Materials

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1. Analysis of the Instrumental Time Lag for a Thick Dense SBS Film and an Sbs TFC Membrane

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SI Figure 1 gives a comparison of the time lag both , permeance, and permselectivity of a thick SBS film and a TFC SBS membrane. The trends for membranes are very similar and the small difference in the selectivity is probably due to the slightly different properties in bulk and in thin films. The virtually constant permeability and selectivity as a function of the sweep flow rate suggest that polarization phenomena in the permeate side are negligible, as this would have led to a decrease in permeability of the most permeable gas (CO2) at the lowest sweep flow rates. 80 70 10

Permeance (GPU)

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Time Lag (s)

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SI Figure 1. Effect of the sweep flow rate on the time lag (a), the permeances (b), and the permselectivity (c) of a fast 5 µm thin film composite membrane (spheres) and a slower 159 µm thick dense film (diamonds) for the N2/O2/CO2 80/10/10 vol % mixture. Sweeping gas at atmospheric pressure.

Membranes 2018, 8, x; doi: FOR PEER REVIEW

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Membranes 2018, 8, x FOR PEER REVIEW

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2. Study of the Effect of Slow Pressure Increase on the Instrumental Time Lag 7

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SI Figure 2. Increase of the feed pressure upon switching of the six-way feed valve from Argon purge to the 80/10/10 vol % N2/CO2/O2 mixture (a), corresponding permeation curves for O2 (b), and resulting instrumental time lag (c) determined with an SBS TFC membrane (area 1.77 cm−2). Feed flow rate 200 cm3STP min−1 and sweep flow rate 30 cm3STP min−1.

Membranes 2018, 8, x FOR PEER REVIEW

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3. Reaction of the Permeate Composition on Changes in the Feed Pressure

Feed flow rate (cm3 STP min-1)

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Measurement time (h)

(a) Permeate flow rate (cm3 STP min-1)

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Measurement time (h)

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SI Fig. 3. Profile of the feed flow rates and feed pressure (a), and the permeate flow rates (b) as a function of time for the SBS thin film composite membrane with a 80/10/10 vol % N2/CO2/O2 mixture.

Membranes 2018, 8, x FOR PEER REVIEW

4. Mixed Gas Diffusion in the Polymer of Intrinsic Microporosity PIM-SBF-1 7

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SI Figure 4. Comparison of the increasing feed pressure as a function of time for individual pressure increase ramps (a) and for stepwise increasing pressure (b) for 2088 days aged sample SBF with the gas mixture CO2/CH4 35/65 vol %.

5. Schematic Concentration Profile Development in Three Subsequent Pressure Steps

SI Figure 5. Schematic representation of the development of the concentration profiles in the membrane after its first exposure to the gas and during two subsequent pressure increase steps.

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6. Apparent Time Lag during Pressure Increase Steps and Pressure Decrease Steps 350

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CH4

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SI Figure 6. Individual time lag for CO2 and CH4 in a 2088 days aged sample of PIM-SBF with a stepwise pressure increase (full circles). The empty circles show the corresponding points for the pressure decrease steps. Points of the instrumental time lag Θ0 for N2, O2, and CO2 overlap.