The enhancement of oxygen flux on Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSCF) hollow fibers using silver surface modification

Dense ceramic oxygen permeable membranes and catalytic membrane reactors

“…The maximum enhancements of the oxygen fluxes through the LSCF and Ag modified membranes were found to be at 800°C with an amount of 9.3 and 17.8 times of the original oxygen permeation flux, respectively [116]. However, the surface loading of the Ag catalyst was not homogenous and Ag species were concentrated on the grain boundaries of the perovskite [117]. Also Pd coating on the LSCF hollow fibers was used to reduce the resistant of the surface exchange reaction, which increased the oxygen permeation flux up to 3.5 times of the unmodified fibers [118].…”

Analysis of oxygen exchange-limited transport and chemical stresses in perovskite-type hollow fibers

“…Separation of oxygen from the feed air starts on the outer surface of the membrane, and, as a consequence, oxygen is transported via oxygen vacancies through the membrane thickness under the driving force of oxygen chemical potential gradient. The oxygen flux through the hollow fiber membrane is affected not only by bulk transport of oxygen ions, but also by oxygen exchange processes on membrane surfaces [29], i.e., the coupling effects of bulk transport and surface exchange need to be considered. Thus, the total oxygen permeation depends on three processes: (1) oxygen exchange on the outer membrane surface (shell side), (2) bulk transport, and (3) oxygen exchange on the inner membrane surface (lumen side).…”

“…These experimental data are shown in the Table 1. Using both types of these data the oxygen partial pressure dependence of membrane surface exchange coefficient at the permeate side can be identified as follows: (29) where k ¼ 22.926 Â 10 À3 , B ¼ 1.83 Â 10 À4 ms À1 bar Àk . It is seen ( Table 1) that there is a good correlation between the experimental values of b ex and model predictions by Eq.…”

Oxy-combustion of liquid fuel in an ion transport membrane reactor

“…Recent research papers [29][30][31] indicate that there are substantial efforts to enhance the performance and the stability of BSCF based membranes, especially hollow fiber membranes [30,31]. Though, there is little work conducted on ITMs performance under reactive conditions, there is absolutely no work carried out on ITMs utilizing liquid fuels as oxidizers.…”