A series of praseodymium added CeO2（ZrO2）/TiO2 catalysts separately prepared by methods of sol-gel and impregnation were tested for selective catalytic reduction of NO, and characterized by X-ray diffraction （XRD）...A series of praseodymium added CeO2（ZrO2）/TiO2 catalysts separately prepared by methods of sol-gel and impregnation were tested for selective catalytic reduction of NO, and characterized by X-ray diffraction （XRD）, N2-brumauer-emmett-teller （N2-BET）, NH3-temperature programmed desorption （NH3-TPD）, H2-temperature programmed reduction （H2-TPR）, PL spectra, Ra-man spectra, electron paramagnetic resonance （EPR） and X-ray photoelectron spectroscopy （XPS）, respectively. Influence of prepara-tion method on catalytic performance was studied. Results showed that the influence of Pr addition on catalytic performance of the CeO2（ZrO2）/TiO2 catalysts was different between the sol-gel method and the impregnation method. The Pr addition tended to interact with TiO2 and formed the structure of Ti-O-Pr in the sol-gel method while it was more likely to interact with CeO2 forming the struc-ture of Ce-O-Pr in the impregnation method. The total acid amount and redox properties of the catalysts prepared by sol-gel method decreased with the addition of Pr element, which resulted in decrease of catalytic activity. In contrast, the Pr-added catalyst prepared by impregnation method was found to possess easier reducibility, more total acid amount and higher proportion of Ce3＋ species, which was favourable for higher catalytic activity.展开更多
采用共沉淀法制备了Zr0.5Ti0.5O2载体材料,将其掺杂在CeO2-Al2O3(CA)基催化剂中,并对其催化活性进行了超临界裂解测试,采用全自动吸附仪、X射线衍射(XRD)、透射电镜(TEM)、程序升温脱附(TPD)等方法对催化剂进行了表征.实验结果表明,催...采用共沉淀法制备了Zr0.5Ti0.5O2载体材料,将其掺杂在CeO2-Al2O3(CA)基催化剂中,并对其催化活性进行了超临界裂解测试,采用全自动吸附仪、X射线衍射(XRD)、透射电镜(TEM)、程序升温脱附(TPD)等方法对催化剂进行了表征.实验结果表明,催化剂能够明显降低裂解反应的温度,600°C CA基催化剂产气率是热裂解的2.8倍,掺杂Zr0.5Ti0.5O2载体材料的CA基催化剂是热裂解的4.0倍,650°C时,掺杂Zr0.5Ti0.5O2载体材料的CA基催化剂热沉提高了0.55 MJ kg 1.BET结果表明,掺杂Zr0.5Ti0.5O2载体后催化剂出现双孔结构,部分小孔的出现使得乙烯的选择性提高;NH3-TPD结果表明,掺杂Zr0.5Ti0.5O2载体材料后,催化剂强酸位的酸量增加了4.0倍,催化剂表现出更强的表面酸性和更集中的强酸酸中心密度,有利于裂解多产烯烃.展开更多
基金supported by National Key Research and Development Program of China(2016YFC0205500)National Natural Science Foundation of China(51272105)+1 种基金Jiangsu Provincial Science and Technology Supporting Program(BE2013718)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘A series of praseodymium added CeO2（ZrO2）/TiO2 catalysts separately prepared by methods of sol-gel and impregnation were tested for selective catalytic reduction of NO, and characterized by X-ray diffraction （XRD）, N2-brumauer-emmett-teller （N2-BET）, NH3-temperature programmed desorption （NH3-TPD）, H2-temperature programmed reduction （H2-TPR）, PL spectra, Ra-man spectra, electron paramagnetic resonance （EPR） and X-ray photoelectron spectroscopy （XPS）, respectively. Influence of prepara-tion method on catalytic performance was studied. Results showed that the influence of Pr addition on catalytic performance of the CeO2（ZrO2）/TiO2 catalysts was different between the sol-gel method and the impregnation method. The Pr addition tended to interact with TiO2 and formed the structure of Ti-O-Pr in the sol-gel method while it was more likely to interact with CeO2 forming the struc-ture of Ce-O-Pr in the impregnation method. The total acid amount and redox properties of the catalysts prepared by sol-gel method decreased with the addition of Pr element, which resulted in decrease of catalytic activity. In contrast, the Pr-added catalyst prepared by impregnation method was found to possess easier reducibility, more total acid amount and higher proportion of Ce3＋ species, which was favourable for higher catalytic activity.
文摘采用共沉淀法制备了Zr0.5Ti0.5O2载体材料,将其掺杂在CeO2-Al2O3(CA)基催化剂中,并对其催化活性进行了超临界裂解测试,采用全自动吸附仪、X射线衍射(XRD)、透射电镜(TEM)、程序升温脱附(TPD)等方法对催化剂进行了表征.实验结果表明,催化剂能够明显降低裂解反应的温度,600°C CA基催化剂产气率是热裂解的2.8倍,掺杂Zr0.5Ti0.5O2载体材料的CA基催化剂是热裂解的4.0倍,650°C时,掺杂Zr0.5Ti0.5O2载体材料的CA基催化剂热沉提高了0.55 MJ kg 1.BET结果表明,掺杂Zr0.5Ti0.5O2载体后催化剂出现双孔结构,部分小孔的出现使得乙烯的选择性提高;NH3-TPD结果表明,掺杂Zr0.5Ti0.5O2载体材料后,催化剂强酸位的酸量增加了4.0倍,催化剂表现出更强的表面酸性和更集中的强酸酸中心密度,有利于裂解多产烯烃.
