A Dual‐Phase Ceramic Membrane with Extremely High H₂ Permeation Flux Prepared by Autoseparation of a Ceramic Precursor

Abstract

A novel concept for the preparation of multiphase composite ceramics based on demixing of a single ceramic precursor has been developed and used for the synthesis of a dual-phase H2 -permeable ceramic membrane. The precursor BaCe0.5 Fe0.5 O3-δ decomposes on calcination at 1370 °C for 10 h into two thermodynamically stable oxides with perovskite structures: the cerium-rich oxide BaCe0.85 Fe0.15 O3-δ (BCF8515) and the iron-rich oxide BaCe0.15 Fe0.85 O3-δ (BCF1585), 50 mol % each. In the resulting dual-phase material, the orthorhombic perovskite BCF8515 acts as the main proton conductor and the cubic perovskite BCF1585 as the main electron conductor. The dual-phase membrane shows an extremely high H2 permeation flux of 0.76 mL min(-1) cm(-2) at 950 °C with 1.0 mm thickness. This auto-demixing concept should be applicable to the synthesis of other ionic-electronic conducting ceramics.

Innovative steam methane reforming for coproducing CO‐free hydrogen and syngas in proton conducting membrane reactor

“…The hydrogen permeability of a proton conducting ceramic membrane has a significant effect on the performance of membrane reactor. In a previous study, 36 Cheng brane was found to exhibit a high hydrogen permeation flux. 36 In this work, the dual-phase BCF8515-BCF1585 dense ceramic membrane was used for in-situ removal of the hydrogen generated from SMR process due to its high hydrogen permeability.…”

“…In a previous study, 36 Cheng brane was found to exhibit a high hydrogen permeation flux. 36 In this work, the dual-phase BCF8515-BCF1585 dense ceramic membrane was used for in-situ removal of the hydrogen generated from SMR process due to its high hydrogen permeability. 16,31,32 In this work, by coupling steam methane reforming with in-situ H 2 removal in a proton conducting membrane reactor, the coke deposition is expected to be inhibited in the presence of steam on methane side.…”

High-flux dual-phase percolation membrane for oxygen separation

“…In the following, we study the microstructures of all sintered 50CPO-50PCFO, 60CPO-40PCFO and 75CPO-25PCFO samples at the optimal sintering condition. two perovskite oxides [49], which was attributed to the large differences between the radii of Ce 3+ and Ce 4+ (1.15 and 1.01) and Fe 2+ , Fe 3+ , and Fe 4+ (0.92, 0.785, and 0.725) [50,51]. The auto separation of BCF8515 is of great benefit for the H2 permeability.…”

Dual‐phase membrane reactor for hydrogen separation with high tolerance to CO2 and H2S impurities

“…However, their wide applications in industry are limited by high price, hydrogen embrittlement, and easily poisoned by CO and H 2 S . Proton‐conducting ceramic membranes exhibit a high hydrogen permeation selectivity but much lower hydrogen fluxes (usually 0.01–1 mL cm −2 min −1 ) . Furthermore, it is a significant challenge for the typical (Ba/Sr)CeO 3 ‐based proton‐conducting ceramic membranes to maintain the perovskite structure and permeation performance under a hydrogen atmosphere containing H 2 O(g), CO 2 , and H 2 S …”