Advanced methods for analysis of mixed gas diffusion in polymeric membranes

A comparative study between single gas and mixed gas permeation of polyether-block-amide type copolymer membranes

“…37-51 at 25-50 ⁰C) than for the Pebax® 1657 membranes (ca. [26][27][28][29][30][31][32][33][34][35][36][37] what can be justified by the higher PE/PA ratio for the former polymer.…”

“…Permeability (P) was calculated using the slope of the p d -t curve in the stationary region. The diffusion coefficient (D) was estimated through the time lag method and the solubility coefficient (S) was obtained from P and D [30,31]. A more detailed explanation of the time lag method can be found in Fig.…”

Outstanding performance of PIM-1 membranes towards the separation of fluorinated refrigerant gases

“…Thus, this transient behavior can be attributed to the time required to stablish a steady permeation rate through the high free volume PIM-1 membranes, which for these large molecules is expected to be much higher than for common noncondensable gases owing to the expected lower diffusivity, a fact that should be confirmed with time lag measurements. For instance, Monteleone et al (2022) [36] determined the CO 2 permeation through a PIM-DTFM-BTrip membrane and considered that a steady permeate flux was achieved from approximately 5 times the value of the time lag (around 120 s), i.e., after 10 min. Accordingly, all F-gas permeability data reported in this work correspond to experimental measurements performed after reaching stable values over time.…”

Modelling Sorption and Transport of Gases in Polymeric Membranes across Different Scales: A Review

“…In the case of mixed-gas sorption, the available studies are discussed in the dedicated section, and are mostly related to CO 2 /CH 4 and CO 2 /hydrocarbon binary mixtures and CO 2 /CH 4 /C 2 H 6 ternary mixtures [24,29,[35][36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54]. For mixed-gas diffusion, CO 2 /CH 4 , CO 2 /N 2 /O 2 , and CO/CO 2 /N 2 /O 2 mixtures have been studied [55][56][57]. Such studies identified and classified differences between ideal and multicomponent selectivity, especially concerning the overall importance of the solubility-selectivity contribution [32].…”