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The inorganic-carbonate dual-phase membrane represents a class of dense membranes that are fabricated using diverse support materials, ranging from metals to ceramics. This dual-phase membrane consists of a porous metal or ceramic support with an introduced carbonate phase within the support pores. Compared with polymer and zeolite membranes, inorganic-carbonate dual-phase membranes exhibit exceptional CO2 selectivity at elevated temperatures (>500 °C), making them an ideal choice for high-temperature CO2 separation in power plant systems. The present paper provides a comprehensive overview of the separation principle, significant models, and preparation techniques employed in carbonate dual-phase membranes for CO2 separation. The present study aims to discuss key factors that limit the CO2 permeation performance and stability of membranes, while also exploring the potential applications of dual-phase membranes in various fields. The identification of key challenges in the future development of the carbonate dual-phase membrane has been highlighted in this work. The future trajectory of research and development should be directed toward overcoming these challenges, encompassing the synthesis technology of membranes, balance optimization of membrane structure and performance, modification of physical and chemical properties of molten carbonate, and advancement in high-temperature sealing techniques, as well as exploration of diverse membrane reactors based on carbonate dual-phase membranes for prospective applications. [ABSTRACT FROM AUTHOR]

SAPO‐34 hollow fiber zeolite membranes are successfully synthesized on α‐Al2O3 hollow fiber ceramic substrates by secondary growth method, and used to separate H2 from a binary mixture (H2, C3H8) or ternary mixture (H2, C3H8, and C3H6) under a wide temperature range (25–600°C) with the aim of using them for propane dehydrogenation (PDH) reactions at high temperature. The results show excellent performance for H2/C3H8 and H2/ C3H8 & C3H6 separation, with high H2 permeance of 3.1 × 10−7 mol/m2/s/Pa and H2/C3H8 selectivity of 41 at 600°C. Additionally, the membrane shows stable performance for 140 hr of H2/C3H8 separation test at 600°C. The high performance of this membrane is mainly attributed to the thin (∼2 μm) zeolite layer and asymmetric‐wall of the hollow fiber support. So far, this membrane offers the highest hydrogen permeation and selectivity for H2/C3H8 separation at high temperature (600°C) compared to those reported in literature. [ABSTRACT FROM AUTHOR]

Abstract: The MOx–CeO2/CuO (M=Co, Mn, Sn and Zn) catalysts were synthesized by the hydrothermal method and characterized by XRD, BET, SEM, H2-TPR and HRTEM techniques. It is found that the MnO2–CeO2/CuO catalyst exhibits the best activity from 75°C to 115°C, suggesting that the addition of Mn is the most effective for improving low-temperature activity. The reasons are that MnO2 improves the dispersion of CeO2 and the textural property of CeO2/CuO catalyst. Moreover, the presence of MnO2 is favorable for preventing the reduction of CuO, and MnO2 also enhances the interaction between CeO2 and CuO. [Copyright &y& Elsevier]

The solvothermal method was used to prepare the CuO precursor with cotton-ball-like morphology in order to obtain the CeO2/CuO catalysts with high BET surface area. The catalysts were characterized via SEM, XRD, H2-TPR, ICP, HRTEM and N2 adsorption–desorption techniques. The study shows that CeO2 and CuO interact on the contact interface. The interaction of oxides switches on CO oxidation at 55 °C and the synergistic effect of interaction also improves H2 oxidation at 95 °C. CO oxidation takes place at the contact interface of CeO2 and CuO. The high BET surface area and good dispersion of catalysts can be more helpful for the presence of accumulated long periphery at interface of CeO2 and CuO than the larger CeO2 particles when most of CeO2 particles pile into the small clusters and distribute on the bulk CuO. The CeO2/CuO catalyst with 1:2 Ce/Cu molar ratio has the highest BET surface area and better dispersion of CeO2 among the catalysts, therefore it display good catalytic activity, selectivity and stability. [ABSTRACT FROM AUTHOR]

Abstract: The hydrothermal in combination with impregnation methods are used to prepare the CeO2/CuO-X catalysts with spherical structure. The catalysts are characterized via SEM, XRD, H2–TPR, HRTEM, XPS and N2 adsorption–desorption techniques. The study shows that the microspheres of CuO consist of the sheet-like CuO and the way of arrangement results in the formation of shell structure. There is a core in the middle of shell structure, which is composed of the nano-sized CuO particles. CeO2 particles are supported on the surface of the CuO microspheres or embedded in the pores of sheet-like CuO. It is found that there is another reason for the decrease of CO conversion above 155 °C except H2 competitive oxidation. It is from the change of the CeO2/CuO catalyst during CO-PROX reaction including the reduction of CuO and the separation of metallic copper from the surface of catalyst. [Copyright &y& Elsevier]