Low temperature hydrogenation of benzene and cyclohexene: A comparative study between γ-Al2O3 supported PtCo and PtNi bimetallic catalysts
Low temperature hydrogenation of benzene and cyclohexene: A comparative study between γ-Al2O3 supported PtCo and PtNi bimetallic catalysts
复制标题
DOI：
10.1016/j.jcat.2008.08.016
复制
发表时间：
2008-10
影响因子：
7.3
通讯作者：
Shuliang Lu;William W. Lonergan;J. Bosco;Songrui Wang;Yuexiang Zhu;You-chang Xie;Jingguang G. Chen
中科院分区：
文献类型：
--
作者：
Shuliang Lu;William W. Lonergan;J. Bosco;Songrui Wang;Yuexiang Zhu;You-chang Xie;Jingguang G. Chen
采用浸渍法在γ-Al 2 O3上制备了负载型PtCo、PtNi双金属和Co、Ni、Pt单金属催化剂，并在低温（273-343 K）和常压下评价了苯和环己烯的加氢反应。傅里叶变换红外光谱（FTIR）和流动反应器研究的结果都表明，PtCo双金属催化剂对苯加氢的活性明显高于PtNi和单金属Co、Ni和Pt催化剂，而PtNi催化剂对环己烯加氢的活性更高。H2化学吸附和H2程序升温还原（H2-TPR）研究结果表明，少量Pt的加入可以提高催化剂的化学吸附量，使Co或Ni更容易还原，特别是对Co基催化剂。扩展X射线吸收精细结构（EXAFS）结果证实了PtCo和PtNi双金属催化剂中Pt-Co和Pt-Ni双金属键的形成，支持了先前表面科学和理论预测的论点，即这两种双金属催化剂将比相应的单金属催化剂具有更高的加氢活性。
Supported PtCo and PtNi bimetallic and Co, Ni, Pt monometallic catalysts were prepared by impregnation method on γ-Al2O3and evaluated for the hydrogenation of benzene and cyclohexene at low temperatures (273–343 K) and atmospheric pressure. Results from batch reactor studies with Fourier transform infrared spectroscopy (FTIR) and flow reactor studies both showed that PtCo bimetallic catalysts exhibited significantly higher activity than PtNi and monometallic Co, Ni, and Pt catalysts for benzene hydrogenation, while PtNi catalysts showed higher activity for cyclohexene hydrogenation. Results from H2chemisorption and H2-temperature-programmed reduction (H2-TPR) studies showed that a small amount of Pt addition could increase the chemisorption capacity and make the reduction of Co or Ni much easier, especially for Co-based catalysts. Extended X-ray absorption fine structure (EXAFS) results confirmed the formation of Pt–Co and Pt–Ni bimetallic bonds in the PtCo and PtNi bimetallic catalysts, supporting the argument from previous surface science and theoretical predictions that these two bimetallic catalysts would have higher hydrogenation activity than the corresponding monometallic catalysts.