title: Manganese-rich MnSAPO-34 molecular sieves as an efficient catalyst for the selective catalytic reduction of NOxwith NH3: one-pot synthesis, catalytic performance, and characterization.
abstract: Manganese-rich MnSAPO-34 molecular sieves were prepared by one-pot synthesis method for NOxabatement using the ammonia-selective catalytic reduction (NH3-SCR) technology and characterized using ICP, BET, XRD, FE-SEM, H2-TPR, NH3-TPD, XPS, and DR UV-Vis analyses. The experimental results indicate that the Mn content and chemical state, as well as the surface acidity, of the MnSAPO-34 molecular sieves significantly enhance their DeNOxefficiency at low temperatures (ca. 200-300 °C). The manganese-rich MnSAPO-34 was synthesized using a combination of triethylamine and diisopropylamine as the structural directing agents and high Mn loading (n(MnO)/n(P2O5) = 0.4). The resulting catalyst exhibits the highest activity among all of the samples with a NOxconversion value of nearly 95% and a N2selectivity that is higher than 90% at 220-400 °C. In addition, this catalyst presents higher NOxconversion than the conventional V2O5-WO3/TiO2catalysts and other SAPO-based catalysts below 300 °C. Furthermore, the analytical results indicate that the manganese species in the catalyst are mainly in the form of a framework Mn(IV), which could play a significant role in the NH3-SCR process as the specific active species. The results suggest that controlling the types and content of the organic amine templates and variations in the surface acidity of the catalysts may significantly enhance the SCR activity at lower temperatures.
authors.affiliation: School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou, 510006, People's Republic of China.
authors.forename: Chenglong
authors.initials: C
authors.lastname: Yu
authors.affiliation: School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou, 510006, People's Republic of China.
authors.forename: Feng
authors.initials: F
authors.lastname: Chen
authors.affiliation: School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou, 510006, People's Republic of China.
authors.forename: Lifu
authors.initials: L
authors.lastname: Dong
authors.affiliation: School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou, 510006, People's Republic of China.
authors.forename: Xiaoqing
authors.initials: X
authors.lastname: Liu
authors.affiliation: School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou, 510006, People's Republic of China. cebhuang@scut.edu.cn.|Guangdong Provincial Key Laboratory of Atmospheric Environment and Pollution Control, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou, 510006, People's Republic of China. cebhuang@scut.edu.cn.
authors.forename: Bichun
authors.initials: B
authors.lastname: Huang
authors.affiliation: School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou, 510006, People's Republic of China.
authors.forename: Xinnan
authors.initials: X
authors.lastname: Wang
authors.affiliation: School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou, 510006, People's Republic of China.
authors.forename: Shengbang
authors.initials: S
authors.lastname: Zhong
mesh_terms: D000641:Ammonia / Q000032:analysis / Q000737:chemistry; D002384:Catalysis; D003080:Cold Temperature; D008345:Manganese / Q000737:chemistry*; D009569:Nitric Oxide / Q000032:analysis / Q000737:chemistry
chemical_list: D009569:Nitric Oxide; D008345:Manganese; D000641:Ammonia
keywords: Manganese-rich; MnSAPO-34 molecular sieve; Nitrogen oxide; One-pot synthesis; Selective catalytic reduction; Surface acidity