Chen Yin, Chen Lin, Liao Yanfen, Chen Zhuofan, Ma Xiaoqian
Guangdong Province Key Laboratory of Efficient and Clean Energy Utilization, School of Electric Power, South China University of Technology, Guangdong, Guangzhou 510640, China.
College of Information and Mechanical & Electrical Engineering, Ningde Normal University, Fujian, Ningde 352100, China.
J Colloid Interface Sci. 2024 Apr;659:299-311. doi: 10.1016/j.jcis.2023.12.150. Epub 2023 Dec 27.
Previous studies have indicated the potential of monometallic-modified TiO catalysts in controlling nitrogen oxide (NO) and volatile organic compounds (VOCs) in coal-fired flue gas. Unfortunately, increasing selective catalytic reduction (SCR) activity under complicated coal-fired flue gas status is tricky. In this study, modified Co-MoWTiO catalysts with multiple active sites were synthesized using the wet impregnation method, which exhibited excellent multi-pollution control ability of NO, benzene and toluene under low oxygen and high SO concentrations. The modification of Mo and Co achieved high dispersion and electron transfer. The interaction between W/W and Co/Co promoted gas-phase O adsorption on the catalyst surface, forming of reactive oxygen species (O). Density functional theory (DFT) calculations informed that the doping of Co effectively enhanced the NH and O adsorption capacity of the catalyst, and Co possessed the maximum adsorption energy for NH and O. Possible pathways of multi-pollution control of NO, CH, and CH were speculated. NH/NH on the Lewis/Bronsted acid site is reacted with intermediates of NO (e.g., NO, nitrite, nitrate) via the Langmuir-Hinshelwood and Eley-Rideal mechanism. The introduction of NO and NH did not disrupt the oxidation pathways of benzene and toluene. Following the Mars-van Krevelen mechanism, CH and CH were progressively mineralized by O into CO and HO.
先前的研究表明，单金属改性的TiO催化剂在控制燃煤烟气中的氮氧化物（NO）和挥发性有机化合物（VOCs）方面具有潜力。不幸的是，在复杂的燃煤烟气条件下提高选择性催化还原（SCR）活性是一件棘手的事情。在本研究中，采用湿浸渍法合成了具有多个活性位点的改性Co-MoWTiO催化剂，该催化剂在低氧和高SO浓度下对NO、苯和甲苯表现出优异的多污染控制能力。Mo和Co的改性实现了高分散和电子转移。W/W与Co/Co之间的相互作用促进了气相O在催化剂表面的吸附，形成了活性氧物种（O）。密度泛函理论（DFT）计算表明，Co的掺杂有效地提高了催化剂对NH和O的吸附能力，且Co对NH和O具有最大吸附能。推测了NO、CH和CH多污染控制的可能途径。Lewis/布朗斯特酸位点上的NH/NH通过Langmuir-Hinshelwood和Eley-Rideal机理与NO的中间体（如NO、亚硝酸盐、硝酸盐）反应。NO和NH的引入并未干扰苯和甲苯的氧化途径。遵循Mars-van Krevelen机理，CH和CH被O逐步矿化为CO和HO。
