State Key Laboratory of Clean and Efficient Coal Utilization, Key Laboratory of Coal Science and Technology, Ministry of Education, Taiyuan University of Technology, Taiyuan 030024, PR China; State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China.
State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, PR China.
J Hazard Mater. 2023 Jul 15;454:131489. doi: 10.1016/j.jhazmat.2023.131489. Epub 2023 Apr 25.
Ce-modified commercial vanadium-based catalysts are still in a rapid development stage in terms of optimizing Hg oxidation performance. Due to the universal property of ceria, it can act as either support or promoter to supported vanadium-based catalysts. However, the introduction mode of Ce on the Hg oxidation is still unclarified. Herein, introducing Ce to vanadium-based catalysts as a promoter (VCe/Ti) plays a more effective role in the Hg oxidation than only doping Ce into TiO support (V/CeTi). It is revealed that the strong interaction between V and Ce increases the orbital hybridization, and reduces the lowest unoccupied molecular orbital (LUMO) of V, which is conducive to adsorbing and activating HCl. The excellent performance of the VCe/Ti catalyst can be ascribed to its superior redox ability, stronger HCl adsorption capacity, abundant surface oxygen vacancies, and the redox equilibrium (Ce + V ↔ Ce + V), which improves electron transfer, and thus the catalytic activity. This work provides the potential application of Ce-modified V-based catalysts for the simultaneous control of NO and Hg in stationary sources.
Ce 改性商业钒基催化剂在优化 Hg 氧化性能方面仍处于快速发展阶段。由于氧化铈的普遍性质，它既可以作为载体，也可以作为负载型钒基催化剂的促进剂。然而，Ce 在 Hg 氧化中的引入方式仍不清楚。在此，将 Ce 作为促进剂（VCe/Ti）引入到钒基催化剂中，在 Hg 氧化中比仅将 Ce 掺杂到 TiO 载体（V/CeTi）中发挥更有效的作用。结果表明，V 和 Ce 之间的强相互作用增加了轨道杂化，并降低了 V 的最低未占据分子轨道（LUMO），有利于吸附和激活 HCl。VCe/Ti 催化剂的优异性能可归因于其卓越的氧化还原能力、更强的 HCl 吸附能力、丰富的表面氧空位以及氧化还原平衡（Ce + V ↔ Ce + V），这促进了电子转移，从而提高了催化活性。这项工作为 Ce 改性 V 基催化剂在固定源中同时控制 NO 和 Hg 提供了潜在的应用。
