物理化学学报 >> 2016, Vol. 32 >> Issue (2): 465-473.doi: 10.3866/PKU.WHXB201511242

论文 上一篇    下一篇

MoP(001)表面苯胺C―N键断裂机理

李邵仁,鲁效庆*(),朱后禹,郭文跃   

  • 收稿日期:2015-08-19 发布日期:2016-01-30
  • 通讯作者: 鲁效庆 E-mail:luxq@upc.edu.cn
  • 基金资助:
    国家自然科学基金(21303266);中国石油科技创新基金(2013D-5006-0406)

Mechanism of C―N Bond Cleavage in Aniline on MoP(001) Surface

Shao-Ren LI,Xiao-Qing LU*(),Hou-Yu ZHU,Wen-Yue GUO   

  • Received:2015-08-19 Published:2016-01-30
  • Contact: Xiao-Qing LU E-mail:luxq@upc.edu.cn
  • Supported by:
    the National Natural Science Foundation of China(21303266);Petro China Innovation Foundation, China(2013D-5006-0406)

摘要:

油品脱氮可以减少燃烧过程中氮氧化物的排放,并且减弱催化剂的中毒现象,过渡金属磷化物因具有高催化活性和优异的稳定性而成为最具应用前景的新型加氢脱氮(HDN)催化剂。本工作基于周期性平板模型,通过密度泛函理论(DFT)计算研究了苯胺在磷化钼(MoP)(001)表面的吸附以及C―N断键机理。结果表明在MoP(001)表面,苯胺吸附以平躺吸附构型为主,有较大的吸附能, C―C键和C―N键均被吸附活化;苯胺C―N键的直接断裂路径主要起始于与共吸附H2发生反应,产物为苯和氨,吸附的环己胺的C―N键断裂主要路径是环己胺与共吸附的H发生反应脱去氨基,生成产物为环己烯和氨。

关键词: 磷化钼, 苯胺, 加氢脱氮, 碳氮键, 密度泛函理论

Abstract:

Denitrogeneration of petroleum products can reduce NOx emission during combustion, and relieve the poisoning of catalysts. Because of their high catalytic activities and excellent stabilities, transition metal phosphides exhibit great potential as novel, promising hydrodenitrogeneration (HDN) catalysts. Based on a periodic slab model, we investigated the adsorption and C―N bond cleavage mechanism of aniline on MoP(001) surface by density functional theory (DFT) calculations. The results show that aniline adsorption prefers a flat configuration, with larger adsorption energies, in which the C―C and C―N bonds are activated. The direct C―N bond cleavage mechanism of aniline proceeds mainly via deamination with co-adsorbed H2, producing benzene and ammonia. The C―N bond cleavage mechanism for adsorbed cyclohexylamine proceeds via deamination, with co-adsorbed H, and the main products are cyclohexene and ammonia.

Key words: Molybdenum phosphide, Aniline, Hydrodenitrogeneration, C―N bond, Density functional theory