Permeation, sorption, and diffusion of CO2-CH4 mixtures in polymers of intrinsic microporosity: The effect of intrachain rigidity on plasticization resistance
KAUST DepartmentAdvanced Membranes and Porous Materials Research Center
Physical Science and Engineering (PSE) Division
Chemical Engineering Program
KAUST Grant NumberBAS/1/1323-01-01
Permanent link to this recordhttp://hdl.handle.net/10754/670092
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AbstractCO2-CH4 mixed-gas sorption and permeation properties of a ladder polymer (PIM-Trip-TB)were measured experimentally at 35 °C to interpret nonideal transport behavior of polymers of intrinsic microporosity (PIMs). Both CH4 and CO2 mixed-gas solubilities were lower than those in the pure-gas environment mainly due to competitive sorption. In the range of pressures tested, the CO2/CH4 mixed-gas solubility selectivity of PIM-Trip-TB coincided on average with the value at infinite dilution, and at all pressures, it was higher than the pure-gas solubility selectivity. Because CO2 diffusion coefficient was found insensitive to mixture effects, we inferred that the increased diffusion coefficient of CH4 and the consequent loss of CO2/CH4 permselectivity in mixture environment were correlated to CO2-induced alteration of the selective diffusion domains of PIM-Trip-TB. Similar effects were also found for PIM-1 by an analysis of pure- and mixed-gas experimental permeation and sorption data. The increase of CH4 mixed-gas diffusion coefficients from the pure-gas values was more pronounced for both PIMs (PIM-Trip-TB and PIM-1)than for a conventional low-free volume polymer 6FDA-mPDA polyimide reported previously; this indicates that the high intrachain rigidity in PIMs cannot restrain unfavorable mixture effects on CO2/CH4 diffusion and permeability selectivity.
CitationGenduso, G., Wang, Y., Ghanem, B. S., & Pinnau, I. (2019). Permeation, sorption, and diffusion of CO2-CH4 mixtures in polymers of intrinsic microporosity: The effect of intrachain rigidity on plasticization resistance. Journal of Membrane Science, 584, 100–109. doi:10.1016/j.memsci.2019.05.014
SponsorsThis work was supported by funding (BAS/1/1323-01-01)from King Abdullah University of Science and Technology (KAUST).
JournalJOURNAL OF MEMBRANE SCIENCE