Oxygen separation through U-shaped hollow fiber membrane using pure CO₂ as sweep gas

摘要

A number of U-shaped K₂NiF₄-type oxide hollow fiber membranes based on (Pr_0.9La_0.1)₂(Ni_0.74Cu_0.21Ga_0.05)O_4+δ (PLNCG) were successfully prepared by a phase inversion spinning process. The PLNCG hollow fiber membranes were then used to investigate the effect of CO₂ concentration in both the sweep gas and the feed air on the oxygen permeation flux. With pure CO₂ as the sweep gas and even 10% CO₂ in the feed air, a steady oxygen permeation flux of 0.9 mL/min·cm2 (STP) is obtained at 975°C during 310 h, and no decline of the oxygen permeation flux is observed. XRD, SEM and EDS characterizations show the spent membrane still maintains the intact microstructure and perfect K₂NiF₄-type phase structure without carbonate, which indicates that the U-shaped PLNCG hollow fiber membrane is a very stable membrane under CO₂ atmosphere and has great potential for the practical application in oxyfuel techniques for CO₂ capture and storage.?2011 American Institute of Chemical Engineers AIChE J, 2012