Chen Yangfan, Zhang Yuchen, Feng Xin, Li Jiangling, Liu Weizao, Ren Shan, Yang Jian, Liu Qingcai
College of Materials Science and Engineering, Chongqing University, Chongqing 400044, PR China.
College of Materials Science and Engineering, Chongqing University, Chongqing 400044, PR China; Chongqing Key Laboratory of Vanadium-Titanium Metallurgical and New Materials, Chongqing University, Chongqing 400044, PR China.
Waste Manag. 2022 Jul 15;149:323-332. doi: 10.1016/j.wasman.2022.06.030. Epub 2022 Jun 27.
As NO has been turning into a crucial environmental problem, NH-SCR technology with relatively simple device, reliable operation and low secondary pollution, has become a widely used commercial and mature de-nitration technology. However, some weaknesses restricted the further application of commercialized VO-WO/TiO NH-SCR catalysts, while FeO-based catalysts have received much attention due to their high thermal stability, passable N selectivity and low cost. In this study, FeO-containing solid waste derived from Zn extraction process of electric arc furnace dust was exploited as the base material for catalyst preparing. Owing to the complementary and synergistic effect of CeO and FeO, 0D CeO quantum dots (CeQDs) with fully-exposed active sites, large specific surface area, and rapid charge transfer have been introduced and deposited onto FeO-containing solid waste nanorods. The in-situ deposition of CeQDs led to the admirable enhancement in NH-SCR catalytic activity, N selectivity and SO tolerance of the extremely low-cost FeO catalyst. Comprehensive characterizations and DFT calculations describing the adsorption of O and NH were applied to analyze the catalyst structure and further investigate the detailed relationship between structural properties and activity as well as reaction mechanism. This work provides new insights for the high-value utilization of iron-containing solid waste and a practical reference for boosting the performance of NH-SCR catalysts by introducing quantum dots.
由于氮氧化物已成为一个关键的环境问题，选择性催化还原（SCR）技术因设备相对简单、运行可靠且二次污染低，已成为一种广泛应用的商业化成熟脱硝技术。然而，一些弱点限制了商业化钒钨/二氧化钛选择性催化还原催化剂的进一步应用，而基于氧化亚铁的催化剂因其高热稳定性、尚可的氮选择性和低成本而备受关注。在本研究中，将电弧炉粉尘锌提取过程中产生的含氧化亚铁的固体废弃物用作制备催化剂的基础材料。由于二氧化铈和氧化亚铁的互补和协同效应，具有完全暴露的活性位点、大比表面积和快速电荷转移的零维二氧化铈量子点（CeQDs）被引入并沉积在含氧化亚铁的固体废弃物纳米棒上。CeQDs的原位沉积导致了极低成本的氧化亚铁催化剂在选择性催化还原催化活性、氮选择性和抗硫性方面有令人钦佩的提高。应用描述氧和氨吸附的综合表征和密度泛函理论计算来分析催化剂结构，并进一步研究结构性质与活性以及反应机理之间的详细关系。这项工作为含铁固体废弃物的高价值利用提供了新见解，并为通过引入量子点提高选择性催化还原催化剂的性能提供了实际参考。
