论文摘要
A combined acid–alkali hydrothermal method was used to prepare fly ash –derived SAPO-34 molecular sieves from a thermal power plant in Inner Mongolia（China）. The specific surface area of the prepared fly-ash-derived SAPO-34 molecular sieves was 579 m2g-1, the total pore volume was about 0.27 cm3g-1, and the pore size was 0.56 nm; the molar ratios of Al2O3:P2O5:SiO2 were 1:0.86:0.45. Cu/SAPO-34 catalysts were prepared by impregnation of low-cost fly-ash-derived SAPO-34 molecular sieves as a support and tested in selective catalytic reduction with NH3（NH3-SCR）. Powder X-ray diffraction（XRD）, N2 adsorption–desorption, X-ray photoelectron spectroscopy（XPS）, H2 temperatureprogrammed reduction（H2-TPR）, NH3 temperature-programmed desorption（NH3-TPD）, electron paramagnetic resonance（EPR）, nuclear magnetic resonance（NMR）, X-ray fluorescence analysis（XRF） and scanning electron microscopy（SEM） were used for catalyst characterization and investigation of the relationships between the catalyst structure and the catalytic activity. The actual silica:alumina ratio of the molecular sieves did not increase with increasing Cu loading, indicating that increasing the Cu loading does not change the original structure of the SAPO-34 molecular sieves. The XRF and NMR results showed that replacement by Cu results in more Si islands. The molecular sieve acidity decreased because of the increased number of Si islands. The NH3-TPD results showed that for the Cu/SAPO-34 catalysts there was a low correlation between the low-temperature activity and the amount of acidic sites. SCR activity is closely related to the location of Cu. The 4.47 Cu/SAPO-34 catalyst has the highest isolated Cu2+ showed the highest NH3-SCR activities（> 90%） at 250–350°C. This work opens up new avenues for recycling fly ash formed in coal-fired power plants（reducing environmental pollution） and developing low-cost SCR catalysts for NOx pollution control.
论文目录
文章来源
类型: 期刊论文
作者: Ge Li,Baodong Wang,Qi Sun,Wayne Qiang Xu,Ziran Ma,Hongyan Wang,Daojun Zhang,Jiali Zhou
来源: Green Energy & Environment 2019年04期
年度: 2019
分类: 工程科技Ⅱ辑,工程科技Ⅰ辑
专业: 环境科学与资源利用,电力工业
单位: National Institute of Clean-and-Low-Carbon Energy
基金: support by the National High Technology Research and Development Program (“863” program) of China (2012AA06A115),China Postdoctoral Science Foundation (2017M610723)
分类号: X773
页码: 470-482
总页数: 13
文件大小: 555K
下载量: 22