摘要
采用两步浸渍法和载体上的原位反应制备了一系列Cs部分取代的Ni-Csx H3-x PW12O40/SiO2催化剂,并用N2吸附比表面积测定(BET)、电感耦合等离子体发射光谱(ICP)、X射线衍射(XRD)、拉曼光谱(Raman)、原位X射线衍射(in situ XRD)、NH3程序升温脱附(NH3-TPD)、H2程序升温还原(H2-TPR)、H2程序升温脱附(H2-TPD)、吡啶吸附傅里叶变换红外(FTIR)光谱等分析测试技术对催化剂进行了表征.以正癸烷为模型化合物,对催化剂的加氢裂化性能进行了评价.结果表明,8%Ni-50%Cs1.5H1.5PW/SiO2催化剂具有最高的C5+收率,明显优于8%Ni-50%H3PW/SiO2催化剂和工业催化剂.随着Cs在Csx H3-x PW中比例的增加,正癸烷的转化率逐渐降低,而C5+选择性则逐渐提高.当催化剂具有合适的孔径时,选择性的提高是由于催化剂酸性的减弱,而转化率的降低则是由于催化剂加氢能力的减弱.
Cs-substituted Ni-CsxH3-xPW12O40/SiO2 catalysts were prepared by two-step impregnation and in situ reaction on the support. The catalysts were characterized by N2 adsorption measurements, inductively coupled plasma atomic emission spectrometry, Raman spectroscopy, in situ X-ray diffraction, NH3-temperature programmed desorption （TPD）, H2-temperature programmed reduction, H2-TPD, and Fourier transform infrared spectroscopy. The hydrocracking of n-decane was used to study the catalytic performance of the Ni-CsxH3-xPW12O40/SiO2 catalysts. The highest C5＋yield obtained for 8%Ni-50%Cs1.5H1.5PW/SiO2 was superior to those of 8%Ni-50%H3PW/SiO2 and an industrial catalyst. The conversion of n-decane slightly decreased and the C5＋selectivity increased with increasing Cs content in the CsxH3-xPW catalysts. Ni-CsxH3-xPW12O40/SiO2 catalysts possessed＆amp;nbsp;relatively large pore sizes, so the improved selectivity might have been due to a weaker acidity of the catalysts. The reduced conversion might have been due to a weaker hydrogenation ability.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
2014年第3期527-534,共8页
Acta Physico-Chimica Sinica
基金
supported by the National Key Basic Research Program of China(973)(2010CB226903)
National Natural Science Foundation of China(21073147,21303140)
Program for Changjiang Scholars and Innovative Research Team in University,China(IRT1036)~~
