Huang Bingjie, Yu Danqing, Sheng Zhongyi, Yang Liu
Department of Environmental Science and Engineering, Nanjing Normal University, Nanjing 210023, China; Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, Nanjing 210023, China.
School of Chemical Engineering and Technology, Wuhan University of Science and Technology, Wuhan 430081, China.
J Environ Sci (China). 2017 May;55:129-136. doi: 10.1016/j.jes.2016.05.038. Epub 2016 Aug 17.
The CeO@TiO core-shell nanostructure catalyst prepared by a two-step hydrothermal method was used for selective catalytic reduction (SCR) of NOx with NH in this study. The catalyst presented the obvious core-shell structure, and the shell was amorphous TiO which could protect the active center from the SO erosion. The catalyst showed high activity and stability, excellent N selectivity and superior SO resistance and HO tolerance. Characterizations such as TEM, HR-TEM, XRD, BET, XPS, NH-TPD, and H-TPR were carried out. The results indicated that the catalyst had large surface area and the active sites were well dispersed on the surface. The NH-TPD, H-TPR and XPS results implied that its increased SCR activity might be due to the enhancement of NH chemisorption and the increase of active oxygen species, both of which were conductive to NH activation. The excellent catalytic performance suggests that it is a promising candidate for SCR catalyst.
本研究采用两步水热法制备的CeO@TiO核壳纳米结构催化剂用于NH选择性催化还原（SCR）NOx。该催化剂呈现出明显的核壳结构，壳层为非晶态TiO，可保护活性中心免受SO侵蚀。该催化剂表现出高活性和稳定性、优异的N选择性以及卓越的抗SO和抗H₂O性能。进行了TEM、HR-TEM、XRD、BET、XPS、NH₃-TPD和H₂-TPR等表征。结果表明，该催化剂具有较大的表面积，活性位点在表面分散良好。NH₃-TPD、H₂-TPR和XPS结果表明，其SCR活性的提高可能归因于NH₃化学吸附的增强和活性氧物种的增加，这两者均有利于NH₃的活化。优异的催化性能表明它是SCR催化剂的一个有前景的候选材料。
