RT info:eu-repo/semantics/article T1 6FDA-polyimide thin-film composite hollow fiber membranes for hydrofluorocarbons and CO2 separations A1 Gutiérrez Hernández, Sergio V. A1 Rico Martínez, Sandra A1 Pardo, Fernando A1 Álvarez, Cristina A1 Miguel García, Jesús Ángel A1 Zarca, Gabriel A1 Urtiaga, Ane K1 Poliimidas K1 Fluorinated polyimides K1 Hollow fiber K1 Thin film composite membrane K1 Hydrofluorocarbons K1 R-32 K1 CO2 K1 2210 Química Física AB Herein, high molecular weight fluorinated aromatic polyimides were assessed for the first time to recoverdifluoromethane (R-32) from its blends with other hydrofluorocarbons and hydrofluoroolefins (R-134a: 1,1,1,2- tetrafluoroethane, R-125: pentafluoroethane, and R-1234yf: 2,3,3,3-tetrafluoropropene). First, a screening was performed with thick flat membranes made of the 4,4’-(hexafluoroisopropylidene)diphthalic anhydride (6FDA) and three different amines: 2,2′-bis(4-aminophenyl)hexafluoropropane (6FpDA), 2,4,6-trimethyl-m-phenylenediamine (TMPD), and 2,3,5,6-tetramethyl-1,3-phenyldiamine (durene). As a result, 6FDA-TMPD was selected for the fabrication of defect-free hollow fiber-thin film composite membranes (HF-TFCM) due to its superior performance for the separation of R-32. These HF-TFCMs showed excellent separation performance to reclaim highpurity R-32 (permeate concentration >99 vol%) from the commercial binary blends R-410A and R-454B (a mixture of R-32 and R-1234yf). In addition, we report for the first time the membrane recovery of R-32 from the ternary blend R-407C (R-32/R-134a/R-125 38.2:43.8:18 vol%). Eventually, the separation of CO2 from synthetic gas mixtures of CO2/CH4 (50:50 vol%) and CO2/N2 (15:85 vol%) was performed for benchmarking, showing that the prepared HF-TFCM kept the separation performance of the 6FDA-TMPD thick membranes. PB Elsevier SN 0376-7388 YR 2024 FD 2024 LK https://uvadoc.uva.es/handle/10324/70912 UL https://uvadoc.uva.es/handle/10324/70912 LA eng NO Journal of Membrane Science, Abril 2024, vol. 698 NO Producción Científica DS UVaDOC RD 20-nov-2024