Enhancing the activity and sulfur resistance of CuFeAlOx catalyst via the structure effect for the simultaneous removal of Hg0 and NO at wide temperature

• Published in: Separation and purification technology 2025-03, Vol.355, p.129579, Article 129579
• Main Authors: Lan, Yang, He, Yunshan, Ma, Wenhui, Chen, Meixing, Zhao, Lingkui, Huang, Yan, Zhang, Junfeng
• Format: Article
• Language: English
• Subjects: Flower-like structures; Hg0 oxidation; NH3-SCR; Simultaneously removing; Sulfur resistance
• ISSN: 1383-5866
• DOI: 10.1016/j.seppur.2024.129579

[Display omitted] •The CuFeAlOx catalysts with different structures were synthesized successfully.•The structure–activity relationship of CuFeAlOx catalysts was investigated.•Different structure effect on the SO2 resistance SCR mechanism was proposed.•Ordered mesopores/macroporous-mesopores are more favourable to promote ammonium sulphate decomposition.•Activated metal sulphates provide a large number of Lewis acid sites. The efficient strategy for improving SO2 resistance and catalytic activity is structural modification. Herein, the CuFeAlOx catalysts with different structures, including one-dimensionally disordered mesoporous nanoparticles structure (CuFeAl-N), one-dimensionally ordered mesoporous nanoparticles structure (CuFeAl-C), three-dimensionally ordered porous honeycomb-like structure (CuFeAl-P) and three-dimensionally ordered porous flower-like structures (CuFeAl-CP), were synthesized via a template method to investigate structure effect on activity and sulfur resistance of the catalyst for simultaneously removing NO and Hg0 at wide temperature. The results showed that the various surface characteristics resulted in distinct behaviours with regards to SO2 tolerance. CuFeAl-CP and CuFeAl-C exhibits excellent SO2 resistance, but CuFeAl-N catalyst presents poor SO2 resistance. The CuFeAl-CP with the flower-like structure possesses large specific surface area, which can expose more active sites and exhibited highly dispersed active component. More importantly, it reacts with SO2 to generate reactive sulfate providing additional acid sites, which significantly promotes high-temperature catalytic performance. One-dimensionally ordered mesoporous and three-dimensionally ordered porous effectively facilitates mass transfer of reactants and ammonium sulphate decomposition, thereby inhibiting surface sulfation and ammonium sulfate species deposition. This work lays the foundation for developing highly efficient SCR catalysts that are tolerant to SO2.