Selectively Impregnating a High-Performance Catalyst on SiC Membranes for Efficient Simultaneous Removal of Dust and NOx

The conventional method for loading catalysts onto membranes often leads to severe gas permeance loss, inducing a trade-off effect between the catalytic efficiency and the gas permeance. In this work, the strategy of optimizing the V2O5−WO3/TiO2 (VWTi) catalyst combined with membrane layer prefilling was developed to selectively impregnate the high-performance VWTi catalyst onto the pore surface of the SiC support layer to achieve efficient simultaneous removal of dust and NOx at a low pressure drop. The surface acidity and redox capacity of VWTi/SiC-C (by the conventional impregnation method) catalytic membranes were optimized by adjusting the WO3 content, thus obtaining a >90% NO removal efficiency at temperatures of 270−350 °C. The approach of membrane layer prefilling avoids the deposition of the catalyst on the SiC membrane layer; thus, VWTi/SiC-P (by the membrane prefilling method) shows an increase of 83% in gas permeance without compromising denitration activity and dust filtration efficiency in comparison with VWTi/SiC-C. Finally, the performance evaluation of the scaled-up prepared tubular VWTi/SiC-P catalytic membrane (length: 1050 mm, outer diameter: 60 mm) for simultaneous dust removal and denitration in actual flue gas purification proves its outstanding application performance. This integrated method provides a practical route for constructing catalytic membranes with high efficiency and low resistance, offering great potential for the synergistic removal of dust and NOx from industrial flue gases.