Preparation and oxygen permeability of Bi26Mo10O69 porous layer modified ionic-electronic mixed conductor on air side

Bi26Mo10O69 nanopowder was prepared by hydrothermal method and used as a surface modification material for oxygen separation membrane to enhance oxygen permeability. Thermal decomposition behavior and phase variation of the precursor were investigated by thermal analyzer (TG-DSC) and high-temperature X-ray diffraction (HT-XRD). Bi26Mo10O69 porous layer was coated on the air side of BaCo0.7Fe0.2Nb0.1O3-δ (BCFN) oxygen permeable membrane by dipping method. In the partial oxidation experiment of coke oven gas (COG), the Bi26Mo10O69-coated BCFN membrane exhibits higher oxygen permeability and CH4 conversion than the uncoated BCFN membrane. When the thickness of BCFN membrane was 1 mm and the COG and air fluxes were 120 and 100 mL/min, the oxygen permeation flux reached 16.48 mL/(min·cm2) at 875 °C, which was 16.96% higher than the uncoated BCFN membrane. Therefore, Bi26Mo10O69 porous layer on the air side will be promising modification coating on the oxygen permeability of BCFN membrane.