Mutual Influence of Mixed-gas Permeation in TR-PBOI Polymer Membranes
| Autor: | Brunetti A., Tocci E., Cersosimo M., Kim J. S., Lee W. H., Seong J. G., Lee Y. M., Drioli E., Barbieri G. |
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| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: | |
| Zdroj: | AMS 12, Jeju Island (South Korea), 02/07/2019, 05/07/2019 info:cnr-pdr/source/autori:Brunetti A.; Tocci E.; Cersosimo M.; Kim J. S.; Lee W. H.; Seong J. G.; Lee Y. M.; Drioli E.; Barbieri G.;/congresso_nome:AMS 12/congresso_luogo:Jeju Island (South Korea)/congresso_data:02%2F07%2F2019, 05%2F07%2F2019/anno:2019/pagina_da:/pagina_a:/intervallo_pagine |
| Popis: | Each component of a gas mixture affects the permeation of the other gases. This mutual influence was systematically investigated for binary gas mixtures that included CO2, N2, CH4, H2, and CO permeating through thermally rearranged poly(benzoxazole-co-imide) (TR-PBOI) membranes [1]. The mixed gas permeation was measured at 35 °C at up to 5 bar of feed pressure. Sorption isotherms of binary mixtures were calculated using the Grand Canonical Monte Carlo approach for quantifying the sorption contribution to the permeation. The diffusivity contribution was estimated by using the permeability value. How and how much CO2 (the most soluble gas) and H2 (the fastest diffusing gas among the gas species tested) affect each other permeation as well as the permeation of the other gases were specifically addressed, including a discussion based on sorption and diffusion contributions. CO2 permeance measured in mixed gases was independent of the other gas in the mixture and did not deviate from its measurements as a single gas, owing to its high affinity with the membrane matrix. However, CO2 significantly affected the permeance of the other gases, reducing H2, N2, CO, and CH4 by 18, 14, 12, and 1.3%, respectively. H2 permeance did not change in mixtures but H2 influenced N2, CO, and CH4, increasing their permeance by 10.5, 2.5, and 1%, respectively. The CO2 concentration in the polymeric matrix was not affected by other gases except for CH4 because of its competitive sorption. In a CO2-containing mixture, the lower N2 permeance resulted mainly from a steep solubility decrease (-90%), whereas diffusivity was mainly responsible for the lower H2 permeance. Consequently, in all CO2- containing mixtures the mixed gas selectivity was greater than the one based on single gases, whereas the opposite trend occurred in all H2-containing mixtures, with a ~6.5% decrease in H2:N2 and H2:CO mixed gas selectivities. In all mixtures, all gases showed a higher diffusivity, which can be attributed to the mutual interaction of gases. In the H2:N2 mixture, both gases showed a linear trend of sorption isotherms, confirming that there was a very low interaction with the polymer and that the permeation was mostly driven by diffusivity. N2 permeability was 10.5% higher than in the single gas, induced by an enhancement in the diffusivity contribution, whereas H2 permeability was practically unchanged. |
| Databáze: | OpenAIRE |
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